What's your planned setup for the Solar Eclipse?

[gregbradley]

I know there is another thread about the eclipse. But I am wondering what would be an ideal setup for imaging it.

I presume a high quality DSLR is the ideal setup with maybe 300mm focal length? Perhaps a bit longer?

Or a lightweight APO around 500-600mm focal length.

I guess its all about FOV. I found my TEC110 was a handy focal length with a full frame camera or even APS camera for the sun during the Venus tranist.

But then the question is do you use some sort of solar Ha filter or simply the Baader solar film (images though are very plain with that white look) or do you simply shoot with fast shutter speed, leave it all on auto so it compensates for the changing light conditions and take lots of shots.
Or do you use a neutral density filter to pull down the brightness so the camera can handle it without blowing out the highlights which I imagine is going to be the issue. There are also circular variable ND filters (basically a pair of circular polarising filters) that you can spin and increase/decrease the amount of filtering easily. With the camera set to auto that may be very flexible.

I'll experiment with one of those with my DSLRs and post the results. I am sure there will be some interest in that.

So a lightweight tracking unit like a Vixen Polarie could be very handy just to keep the sun in the frame as I found getting the sun stable in the frame manually was hard with my TEC110 during the Venus transit.

I was thinking of a time lapse as well at the same time.

Suggestions?

Greg.

[dannat]

Greg I was going to use a polarie for 1 camera, just tripod fr other;
1. Trying o mod my PST, have. Borg helical focuser, repve the guts of the PST & insert helical, then ep holder to 1.25" t adapter -this setup for before during & after
2. Have a Borg 45ed, f/l about 320mm, just to fire shots of totality (pro without solar filter
3. Not sure yet whether bother to do any w/f

[bojan]

LXD75 (2 axis motor drive), loaded with 1000mm+400D for chromosphere & prominences, 300mm+60D for outer corona and chromosphere spectrum (if I have enough time...).
Control of 2 cameras from single lap is a problem I haven't solved yet...

The setup on attached picture is put together just as a part of feasibility study.. it will be much more stable and rigid at the end (I hope..)

[gregbradley]

Impressive setup. Is that transportable though?

Is 1000mm too long or just right? With APS C that is more like 1600mm and that would be quite a magnified view. Perhaps its just right - I am not sure. I used 600mm with the Venus transit and full frame camera and the sun could have been a bit larger. So perhaps an APS sized camera and 600mm would be a nice size. I'll have to test that.




I suppose the key thing here is to practice with it well in advance and iron out any bugs.

Is 320mm a bit short? It might be fine with an APS sized sensor.

A PST gives good Ha images?

Greg.

[bojan]

Greg, 1000mm is 1000mm.. with APS or not..

It should be OK for chromosphere and prominences, as well as for lower corona, as the whole sun will be in the frame, see attached.
For extended corona, I have 300mm (with 60D, also APS size sensor).
Planned control software is Eclipse Orchestrator + DSLR Sutter on the same laptop (to be tested yet)

Transportability-wise, it is 12kg in total.. packed in 3 small suitcases (cabin luggage), tripod is 3kg and will be check-in..

[dannat]

greg its not even APS-c, its mu4/3 so half the size chip of FF

[Poita]

Greg, I don't know of a Ha filter option for a DSLR and standard lens, you would need to shoot through a PST or Lunt scope (i.e. something with an etalon) to get a Ha image.

If you have the $$ a Lunt60 is a great and tiny scope for Ha viewing and imaging, and you can get away with a tiny mount like the iOptron cube.

[dannat]

dont baader make a solar filter of some sort with a SCT (48MM Thread) -

[Retrograde]

Oops - pic upload failed please see subsequent post.

[Retrograde]

I'm thinking of something like this. ED is 700mm & the little Mak is 800mm. Still have to see whether I can get the optical axes parallel which is the next challenge.

[gregbradley]

That looks good. The only thing for me is these Baader solar shots aren't that attractive in that they are kind of mostly whitish. I've used them a few times. But I suppose the Ha filters are very expensive.

Greg.

[gregbradley]

Lunt sounds like an option Peter. I wonder if the variable ND filter may also be good. I have one so I'll do a test and post the results here.

Greg.

[mithrandir]

1000mm on an APS-C gives a FOV 78x52 arcsec for a Canon and a couple of arcsec more on other brands.

1000mm on an a full frame like a 1Dx gives a FOV 127x85 arcsec. 2000mm would give you a sun that almost filled the frame.

I used a Sony a200 (APS-C) on an ED127 for a FOV of 85x57 to shoot the TOV.


Yes Baader film gives a grey/white image. I have one for my C8. I also have a couple of Thousand Oaks glass filters for my ED127 and ST80 which give a yellow image.

[OzEclipse]

Just to pick up on some bits and pieces discussed in this thread:

Variable ND filters
Variable ND filters made from crossed polarizers are not visually safe (I think they pass too much IR) and probably won't give sufficient ND for solar photography. They only go down to a few % transmission. A solar filter is 0.01% to 0.001%. I am assuming you were talking about using them for the partial phases.

If you were thinking of using them for totality, I recommend against this. It's unnecessarily complicating things AND the corona is polarized so as you rotate the filters, different streamers will come into view. you will have a very hard time trying to stack and radially merge these images to make a composite or HDR image.

Using Auto exposure
Works really well for wide field exposures - wider than 28mm where you are trying to capture sky and landscape. It does not work for close ups of the eclipse and corona. At ISO100 & at f8 the inner corona needs about 1/4000. Then just keep increasing the exposure to about 4s to capture out to about 8 solar radii. Note that sky conditions may be brighter than the brightness of the corona at 8 Rs.

Colour of Sun with Baader film
Pictures taken with Baader film can be easily recoloured to any colour.

Filter types
Glass filters are not much good for eclipse photography because you have to refocus for totality after removing them. The Baader film is so thin that the focus remains unchanged. When removed 10-15s before you really don't want to be mucking around with focus.

Baader 48mm filter?
I think you're referring to the Baader solar continuum filter which gives a green image. It must be used with a full ND filter 4 or above and would be difficult to remove before totality, unless you have it on a separate optical system that you won't use during totality. It gives better definition for solar surface detail.

Ideal focal length or field of view
There isn't one. There are reasons for using short, medium and long focal lengths. In my reading of the posts, some writers seem to be thinking about this in terms of photographing the 30 arc minute disc of the Moon. You are not. The corona extends out to to 20 or more degrees diameter. Look at the C3 coronagraph images. I saw 7 degrees of corona visually when at high altitude in November 1994. It has been captured photographically during an eclipse out to about 13 degrees. You need to decide what of the many phenomena you are trying to capture and then decide on the best image scale to capture it.

Mithrandir wrote "2000mm would give you a sun that almost filled the frame." This is true but only if you center the sun in the field. You don't have to. If you are trying to capture inner corona in great detail, you can offset the sun to the edge of field and pick up nearly 1 - 2 solar radii of inner corona.

Conclusion
Whatever you do, don't leave yourself anything to do apart from removing a solar filter during the last 30s before totality. There is so much going on around you, it's not the time to be staring into a camera. Keep it nice and simple.

Joe Cali

[gregbradley]

Great post Joe. Thanks for posting your invaluable experience.

My Nikon D800 has ISO 50 so that may be useful as well. Also it has auto ISO which if coupled with aperture priority mode could work.

If you want to capture those streaming corona then up to 15 radii of the sun would give a calculation for the ideal focal length for that type of shot.

Peter Ward had a nice shot of this from the Libya eclipse. I wonder what focal length lens he used there.

Greg.

[OzEclipse]

Yes sort of 1 solar radius (Rs) is 1/4 degree
15 radii from the limb is 16 from the center and if we assume a symmetrical corona is 32 side to side or 8 degrees. Solar max corona are typically more compact though more symmetrical than a solar min corona which typically has big streamers coming from the equatorial region and little "polar brushes" north and south.

So that's a 100mm lens on APS and a 150mm lens on full frame if I use the short dimension of the sensor.

I don't want to mislead you. Capturing that extent of corona is by no means easy. Druckmullers 2006 image is a composite made from about 230 images taken with 5 lenses 200mm, 400mm, 600mm, 1240mm to 1640mm (GSO RC8) on canon 5D bods.

You can get an idea of the extent and shape of the corona by looking at the LASCO C3 image. But you can't translate where the corona's luminosity will get lost in the sky glow during an eclipse. I think I've seen Peter's shot from 2006. I was referring to one by Miloslav Druckmuller also taken during tse 2006. The Sun was very high in the sky that day. The solar min eclipse was assymetrical so he put the long streamers diagonally.
http://www.zam.fme.vutbr.cz/~druck/eclipse/Ecl2006l/Tse2006l_39r3_102s_26d33_231n_v1/00-info.htm (http://www.zam.fme.vutbr.cz/%7Edruck/eclipse/Ecl2006l/Tse2006l_39r3_102s_26d33_231n_v1/00-info.htm)

Looking at this image again, I think he is measuring the diameter in radii which would double those focal length calcs ie 200mm for APS-C and 300mm for full frame.

One other thing I could have mentioned in my last post. If you are using a camera lens, then auto focus can sometimes work very well providing the camera AF zones lock onto the lunar limb. But I've also seen out of focus images and/or cameras run by computer where the AF couldn't lock and therefore wouldn't fire the shutter. Owner came back at end of eclipse to find no images.

I checked out your astrophotography site today - fantastic work!

Joe

[Paul Haese]

This is my third total and being on mainland Australia I have chose the following options.

I am using my CGE mount for stability. Setup will be around 3 am in the morning to beat out the crowds from our location. Perhaps earlier.

I am using my TSA refractor for white light imaging with my D3 Nikon. Viewing the phases and imaging those with a Lunt wedge. At totality or very near to it I will change this out to image the corona.

For Ha I am using (I hope) my new Lunt LSHa80 with Point Grey Research 2.8mp camera and lap top. I am still working up some ideas about how to sustain power on the beach for the duration of the eclipse.

All piggy backed. It is an imaging challenge, not for everyone but something I want to do.

[Peter Ward]

I used a William Optics 80mm APO and Pentax *istD. WO have a new GT81 which has even better optics...but make sure you get a modded version as early production runs had woeful internal tube reflections which killed contrast.

As I posted elsewhere, I'll be running a Canon 5dMkIII and 500mm L series F4 on a Starlapse this year....which should deliver way less noise, and much better resolution than the non-tracking system I used in 2006.

15 Solar radii would be tough...Miloslav Druckmuller uses unique software
(he wrote it) with highly calibrated flats etc. to get simply amazing dynamic range that I have yet to see replicated.

[DavidTrap]

Peter - have you heard of any success with teleconverters?? I have a 2x converter that I was thinking of using with my Nikon 70-200 F2.8.

I'm wondering if internal reflections might be a problem.

DT

[bojan]

Could you try it.. (on new Moon.. overexposing) and let us know.
But I think the bigger problem will be their own distortions (mainly cushion, coma and CA) they are always adding to existent lens.

[Peter Ward]

I tested a whole bunch of lenses by pointing them at the brightest mrecury vapour streetlight I could find (this replicates what you will see in the "diamond ring" phase pretty well...where the sun is still dammed bright! ) , and trying various exposures and F-stops.

Some camera lenses had horrible flares and reflections.

All I can say it test whatever you are hoping to use long before the eclipse.

I found simple optical systems worked the best...for example, there was not a whole lot of difference in the WO GT81 I tested and my way more expensive L-series Canon 500mm.

Also, don't run out of time ordering telescope stuff...relevant stocks often run out before a major celestial event.

P.S.

Attached an example of the flare you can get during an eclipse...

[bojan]

Yes, simpler, the better.

Perhaps just a good 300-500mm FL achromat (from binos), stopped down to F/11 0r 16 could be the good enough option...

However, personally, i wouldn't be annoyed by those flares, if they are not interfering (being on top of) with the important details of the image - it is obvious they are artefacts of the optical system, and therefore easily ignored (unless one wants a "PERFECT" image)

[DavidTrap]

Thanks for those comments Gents,

Peter - I presume that diamond ring shot would be considered overexposed?? Have you any other examples without overexposure?? Just wondering if the flare was better.

DT

[Peter Ward]

The Diamond ring is a little tricky to capture as the photosphere is significantly brighter than the emerging corona.

The extent to which you can expoose for the corona will depend on the contrast/quality of the optics...in short there is no universal "right" exposure.

The attached image was taken just a second or two later, with a good result.

[multiweb]

Great thread - following with a lot of interest.

@joe: I'm wanting to make a composite of the corona at totality. I have a camera that doesn't support bracketing or computer control but I have bulb mode. Do you think timing various exposures manually within the two minutes of totality would work to make a HDR combine? I intent to use a canon remote and take the whole sequence by hand. :question:

[Peter Ward]

Easy. I manually adjusted corona exposures from 1/2000th through several seconds during the 2006 eclipse. Took lots of pictures...checking each. just kept at it. Many of the other photographers who were taking "automated" sequences had way more data...sadly for them 90% of it was unusable due a failed focus/exposure etc.

[gregbradley]

Yes thats the problem isn't it. If you rely on auto and it lets you down and you only find out after the event - that would be annoying.

Thanks for the info on setups. Some interesting data here.

I am thinking then my TEC110 at 613mm could be handy with a 40D that works so well on it. Then a 150 to 200mm lens on the D800E. Leave it on manual mode, focus and turn the autofocus off, and handle the ISO and exposure times manually. This is where being familiar with your camera will pay big dividends. Knowing where all the buttons are and how to adjust it quickly. Or use live view and you can see how its going to expose straight away.

Greg.

[OzEclipse]

Multiweb,
While Peter's statement is correct, I think he assumed you have a DSLR and didn't ask if your camera is a digital compact? Is it? Does it have manual mode with shutter speed control not bulb?

At f8 ISO 100 you need to shoot every shutter speed from the fastest available 1/4000 sec through to 2 to 4 seconds to do a full range composite. Only a small number of exposures are in the bulb range.

Tell us what camera you have and I sure either Peter or I can suggest something.

Joe

[multiweb]

Cool - was that with *istD?


I have a SONY NEX-5 and a Pentax *istD. I intend to use the Pentax for a widefield timelapse on automatic exposure and have the NEX-5 with a 200mm lens on a polarie with a manual remote to capture the corona at totality.

[gregbradley]

I have a SONY NEX-5 and a Pentax *istD. I intend to use the Pentax for a widefield timelapse on automatic exposure and have the NEX-5 with a 200mm lens on a polarie with a manual remote to capture the corona at totality.[/QUOTE]

I suspect a time lapse on auto exposure will fail. That's because I find DSLRs don't auto expose to a wide enough exposure range for this sort of work.

For example from daylight to nightime transitions. I have done several now. I used aperture priority with an F2.8 lens and also set the camera to auto ISO with minimum and maximum ISO set.

This worked up to a certain point in the twilight and then it was inadequate at night as that would be ISO6400 and 30 seconds and no way will auto expose set the camera to do that. Aperture priority alone may not be enough and auto ISO is only a feature on a few cameras.

DSLRs are engineered mostly for daytime exposures and it shows in the settings available.

A test would be a time lapse from day to twilight levels matching expected light levels with the eclipse.

Greg.

[multiweb]

Thanks Greg. The SONY NEX-5 supports auto ISO in mode A, Aperture priority but that's the one I'll be using for the corona. Will check the Pentax *istD. I did a couple of transitions from day to night. What I did was stay next to the camera and bump the ISO when it got dark then later keyframe and interpolate the transitions in LR Timelapse.

There are a couple of examples here (http://vimeo.com/astropic/videos).

[gregbradley]

That worked great. Good idea.

In my case though I use 30 second exposures and even at ISO50 that is too bright during daylight.
Perhaps I use shutter priority and manually adjust and shutter speed and keep the interval at 10 seconds
between images so I have enough time to do the adjustments.

Greg.

[DavidTrap]

For the record, I tried out my 2x teleconverter today at my daughter's school sports day. It's a bit too soft for my liking, even stopped down :(

Hopefully the FS-60 I ordered on Monday will do the trick!

DT

[multiweb]

My SONY only goes down to ISO200 minimum though. I have this PDF file from our last astro meeting that gives a lookup table for timing depending on what you want to image. They said to double up exposure time as the sun will be low so multiply all exposure times x2.

[Peter Ward]

Yes, the very same...almost famous as it won CWAS and the inaugural S&T Beautiful universe comp that year.

[multiweb]

No pressure then ... :P

[Paul Haese]

Just done a reassessment of my white light gear. I am going to go with my 300mm f2.8 with a 2x teleconverter on my D3. 600mm at f5.6 should produce nice results. My reasons were that my TSA would produce large images of the eclipse but cut off the extended parts of the corona. So I figure the 300 will produce the results I am after. Thoughts anyone?

[Phil Hart]

Assuming I can get all the gear freighted up, I hope to run my FS-102 with 1.4x TC and Tak Epsilon 160 both with 5DMKIIs (1150mm f11 and 530mm f3.3). Might also think about renting a 5D MKIII with a 200mm lens and then be able to screw up three things at once..

Phil

[DavidTrap]

After my experience today with a 2x teleconverter, I'd go with the 300 prime.

The FS-60 will be 374mm focal length which will still only give a ~5mm sized sun on my chip - but definitely allows for a few solar radii.

Bound to be cloudy after I've invested in a new scope and portable mount, taken time of work, organised flights, hotel and hire car as well as spending spent hours testing software, writing a script and rehearsing... :rofl:

DT

[Paul Haese]

Ever shot an eclipse before Phil? I can tell you it is a manic few minutes. Three units is going to have you racing. ;)



I will have to go with manual focus or buy a Nikon TC 2x because the sigma one I have causes the focus to hunt on my prime. I vaguely remember that the 2x is not really suited for this lens, but a 600mm focal length will give a quite large image on the sensor. What went on today? Sorry have not kept up.

You can bank on cloud in Cairns. Lived there for 18 months from '88 to '90 and I am expecting cloud on the day, but being part of the experience and our last two eclipses were cloud affected I see cloud as being part of the excitement factor.

As for software I am going with preset exposures and bracketting. I cannot be bothered with hooking that part of my kit up to yet another computer. Remember the main thing is to enjoy being in the shadow of the moon and seeing the corona.

[Peter Ward]

Actually...I'm looking forward to kicking back for a week in a Port Douglas resort, fresh seafood, scuba diving the reef.....and, maybe.... if it's clear...;)

[Paul Haese]

Yep we have a week at Palm Cove. Looking forward to catch up with people up there and people we met in China. Might catch up Pete if you want.

[gregbradley]

I recall mention of a 1.6 teleconverter that did not affect image quality much. I think it may be a newish Nikon product.

Greg.

[DavidTrap]

Offloaded my 2x teleconverter last night - lasted <5mins on eBay - must have underpriced it! Also sold a lens and a telescope. I'm cash-flow positive on Astronomy purchases - well at least for this week!

DT

[h0ughy]

ok here is one of what i will be using - canon 650D and 400mm f5.6 L Canon.

this was very quickly talken this afternoon before i had to hand it back to Mr Alder.

it seems a nice size to show some detail and the corona

[gregbradley]

That's good Dave. That is what I would consider an ideal image scale.

So for a full frame camera that would be 640mm if its a 1.6X crop factor which is what my
TEC110 is close to.

Greg.

[h0ughy]

yes. i had an offer to borrow a 2x converter but i am not sure about using it?

[Omaroo]

Which TC was that David? My old TC-300 is fantastic. Clear as a bell. :shrug:

[DavidTrap]

TC-20EIII - latest 2x. I think I was asking too much to expect crisp images through a 70-200 zoom and 2x converter. I think I am used to the quality of images we see through telescopes and the teleconverter/zoom lens combination doesn't really compete for sharpness. I tried some lunar photography and it didn't impress me, so rather than be disappointed at the eclipse I used it to justify the FS-60!

DT

[Phil Hart]

thanks paul. not seriously shot a solar eclipse before but i have done a little bit of photography ;). have seen a solar eclipse in africa so not too worried about compromising the visual experience a little this time, although will certainly not be touching the cameras during the two minutes. if the laptop/eclipse orchestrator control etc don't work so be it.. i won't be trying to fix it during totality! (or even five minutes beforehand).

had about six cameras running during a lunar eclipse last year so ok with planning/prepping a lot of gear and doing a lot of running between them (much slower timescales of course, but a lot less automated as well).

interested to hear tales though from experienced eclipse photographers. assuming you check focus and settings half an hour before totality, remove filters one minute beforehand etc, does eclipse orchestrator work reliably so that you don't end up touching much during totality?

Phil

[h0ughy]

was testng the balance and setup this evening

[Paul Haese]

Phil, not suggesting that you have not done enough photography mate ;). I will not be using any automation like that. Things like that are prone to failure. Manual all the way myself. I have the bracket settings already sorted with the coronal exposure shots. Should shoot about 150 frames during the eclipse if the sky is clear. If not I will sit back and have a drink in the dark.

[h0ughy]

ok just to prove that things are working i did a "live test" . they are not Oscar quality:rofl:

setting up the software (http://youtu.be/THL9cfBJTvg)

and executing it (http://youtu.be/P0cV4XR8Wag)

I suppose the thing here is that the cameras are actually running a similar script. this will be left alone for the eclipse once setup. I will have the 650D on the polarie with a 50mm lens so will be operating with a scripe running from Eclipse orchestrator running on windows

[Phil Hart]

Thanks Paul. Interesting to know that you don't have high confidence in the automation. I figure whatever happens I'm going to learn a lot! cheers to drinking in the dark at 6:40am in november! :lol:

[colinmlegg]

Phil, if you do a few dry runs you should be fine. As you know, eclipse orchestrator was the controller I used for my 12 day shoot and I only had 3 hiccups due to loss of USB control in that time. Just make sure you have good quality USB cables, adequate power, maybe invest in a small usb GPS for timing (eclipse orchestrator works fine with these and the're accurate to 1 second), leave enough time between shots for usb adjustments, or use a serial cable for remote triggering for maximum frame rate.

If you've done enough test runs you can sit back, relax, let it do it's thing and enjoy the show :)

[AstralTraveller]

OK. I had the rig all together tonight for the first time and it looks like it should work. I have a 400D and a (borrowed) 600D with a 70-200 f/4L and a 400 f/5.6L on a long dovetail bar mounted on a Vixen Sphinx. I'm yet to decide which body to pair with which lens. Advice welcome!

Eclipse Orchestrator talks to the USB GPS and to each of the cameras. Immediate jobs are: by full version, arrange a hub, arrange an inverter and battery etc (have most of that), small job on the dovetail, write scripts, do test runs, do more test runs. Stay calm.

[bcoote]

[QUOTE=Paul Haese;895048]This is my third total and being on mainland Australia I have chose the following options.

I am using my CGE mount for stability. Setup will be around 3 am in the morning to beat out the crowds from our location. Perhaps earlier.

Hi Paul
I am taking an EQ6 with Canon 5D Mk11 on an FSQ-106EDX with Reducer (380mm) and will run exposure sequences with a Phottix timer. I am only trying for corona images.
I am hoping to shoot from the beach around the centre-line if possible and setup early also but with saltwater crocs up there this is a worry. Where are you hoping to shoot from Paul?
Brian Coote

[DavidTrap]

WHAT THE????

We're wary of brown snakes at Leyburn, but this is taking things to a whole new level!

DT

[bcoote]

Yep, Saw a program where they tested salties bite strength. About 1500 lbs from memory. There is no way I want one nibbling on me in the dark, or the light for that matter.

With setting up the mount on a beach in the dark has this problem. If set up with mount, deep cycle battery etc. you can hardly leave it there, but hanging around in the dark on a beach up there has a real element of risk. Perhaps having a fair crowd there would be the greatest protection, the lions would probably take one of the fatter wildebeest.

I assume a polar alignment using a compass setting and latitude angle will be sufficient for the exposure times involved.

Brian Coote

[OzEclipse]

[QUOTE=bcoote;897653]

A Cairns local I know told me yesterday that a dog was taken by a croc at Kewarra Beach.

Aside from the real risk of crocs, read the article about tides on my web site. http://joe-cali.com. Tides article is linked from the home page.

Oak beach is one of the prime candidates to be closed by the authorities on safety concerns.

It matters little where you are located up and down the coast over quite a long distance. The limb corrected duration of totality only varies by a few seconds between Smithfield & the Cairns northern beaches to the beaches north of Port Douglas.

When observing the 2002 eclipse from Cameron Corner, the legs on the pier of my equatorial mount which have a much greater surface area than any commercial tripod EQ mount wouldn't stop sinking into the sand. If you do brave the crocs, tides and crowds to sit on the beach, bring some large boards to put under the tripod legs or else you might get that sinking feeling.

For what it's worth, in 2001, I spent 2 hrs photographing Baboon's at sunrise in South Luangwa National Park all the while being stalked by a croc. Taunted a hippo to make him testy. I've stood face to face metres from grizzly bears and been charged by moose hiking in Alaska. You could say I am very comfortable being part of the food chain but I like to see them coming so I can react appropriately.

However, I wouldn't dream of sitting on a beach in the dark hoping the croc takes someone else in the crowd on the morning of the 14th.

Joe Cali

[Paul Haese]

Brian as being a former resident of Cairns I know where Crocs reside. For the most part they stick to the estuaries but will occassionally go onto a beach. However, they tend to be a bit like snakes, they don't really like humans and will shy away from them most of the time in populated areas. Especially when you consider that there will be lots of people about making noise. I don't think there will be much to worry about. Just one of the locals having a little lend of you.

Joe I had thought of the boards a couple of weeks ago, even compact sand will slowly give way and that might not be a good thing during an eclipse.

[OzEclipse]

Paul Haese wrote :


Paul,
No she wasn't, unless you think the Cairns Post is in on it as well.
http://www.cairns.com.au/article/2012/09/21/234097_local-news.html


My old EQ mount had custom cast aluminium legs 40mm wide 800mm long. Yet it sank into the desert sand easily and quite unevenly ie one leg sank more than the others. As it did, more weight was transferred onto it so that the mount kept leaning over more and more. I just had to work with it, keep leveling and and keep correcting the mount pointing position. I was shooting images for a feature story on eclipses for Australian Geographic and hence couldn't afford to fail. The total eclipse from Cameron Corner was only 25s duration so once we were into totality, it didn't have time to move. The problems encountered were during the partial eclipse. By eclipse end, the legs had sunk about 200mm into the sand.

Joe

[bcoote]

Paul,
The boards for the feet are a good idea. Essential really. I imagine 150mm square boards would be big enough. I will add those to my gear.
My only SE was watching in the desert between Woomera & Tambo in 2002 and mount feet sinking was about the only problem I didn't have.

Joe,
Been over your pages and appreciate the wealth of info you are giving us and the experience that went into accumulating it. I will want to pick your brains later on exposure bracketing for coronal images with my setup.
Took a few test shots of the moon last night and 380mm FL with the full frame 5D is as long a focal length as I would possibly want for corona shots. Best exposure was 1/400 sec @ 800 ISO through the FSQ with reducer.

Looking at the moon size I would want at the very minimum 1000 mm FL for full frame shots of prominences but won't be going down that track.

Thanks for the info, Brian Coote

[gregbradley]

One thing to keep in mind with DSLRs is that maximum dynamic range of these DSLRs is always at base ISO - ie ISO100.

Depending on the brand and model that then falls off fairly quikcly so a doubling of ISO often means a hlaving of dynamic range.

Some of these eclipse shots seem to have extremely large dynamic range (the diamond ring for example).

So it would be a better strategy to use lower shutter speed before you use high ISO.

Up to ISO400-800, again depending on the camera, dynamic range should not be affected too much.

Greg.

[bcoote]

Hi Greg,
I have never used my Canon 5D for astronomy. The tonal graduations on these new chips are really awesome to me. At ISO 1600 shots taken in Cathedrals (and the Mosque in Cordoba Spain) showed more detail than I was seeing with my naked eye.
Using a Canon D60 in 2002 for solar prominences was the only time I have used a DSLR for Astro use.

If ISO 1600 cut the dynamic range to 1/16 of what is possible you would expect pretty ordinary results I would think. I have always assumed it was a matter of the amplifier factor applied to the basic image. I know if I increased the Canon D60 to ISO-800 I got visible noise but cannot see any apparent noise in the 5D at ISO-1600.

But this was all an assumption on my part and something I will have to resolve before our SE.
For flares etc the ISO can easily stay at 100 but for corona images having the highest clean ISO setting has distinct advantages.

Thanks for the input, I will try and further check this out.
Brian Coote

[bcoote]

Just looked up a Cnet review
http://news.cnet.com/8301-11386_3-57415773-76/canon-5d-mark-iii-underwhelms-on-sensor-test/
On their tests the Ev drops from 14 at ISO-100 to Ev 10.5 at ISO-1600
I have the Mk: 11 which is slightly worse than this.

Despite this I will still probably go for 400-800 ISO as I feel I am only looking for a limited portion of the data unlike say galaxies where you have everything from no signal to oversaturated in the one image group.
But I am certainly open to correction on this.

Joe Cali would you mind telling us what ISO setting you recommend for corona images?

Brian Coote

[OzEclipse]

In my film days, I used ISO 400 pro-color neg film. Wedding photographer film because it had a wider exposure latitude. Since going digital, I always use the lowest ISO - either 80 on my new camera or 100 on my older camera.

Optical systems are f6-f8

Shutter speeds :
Every shutter speed in 1 eV increments from 1/1000-1/60 for diamond ring
Every shutter speed in 1 eV increments from 1/4000 - 4s for corona.
Earth shine - 8s

The corona has an enormous dynamic range - much bigger than a galaxy.

My best composites are stacks of all 14 stops or 15 if you include the Earthshine and I still struggle to control the contrast.

The dynamic ranges in eV determined by DxO labs (I imagine the CNET tests are similar) don't translate directly to usable stops of exposure latitude on a camera. They are purely a mechanism for comparing sensors. Don't for a moment think you can get a practical 14 eV dynamic working range out of an image even if the sensor test indicates a 14eV range. The usable range is still probably only 6-8eV.

Joe

[bcoote]

Gee Joe! Talk about destroy my assumptions. And now is the time to do it not after I get to Cairns.
I want to try and get this straight in my head.
If you would tell me where I am off track for my revised sequence please.

Canon 5D Mk 2 on Tak FSQ106-EDX with Tak Reducer > 385mm @ F 3.64 on EQ6

1: Canon in LiveView with mirror Locked up

2. ISO set to 100

3. This is the falling off the cliff bit. How do I run a full shutter sequence from 1/4000 to 4 secs. Twice if possible.

I have just got a Phottix timer from Hong Kong but as far as I can see the maximum number of bracketed exposures is 7 at one stop steps. If I want a 4 sec longest exposure this would only give me from 1/60 to 4 secs.

Is there a PC program I can run off a laptop to give 1/4000 to 4 secs limited only by the speed of writing to the card?

I assume (again after being wrong every time before) that the shortest exposures are to capture the corona close to the sun, and so on further out from the sun???

I will try and limit myself to no more than 5 questions (and 2 or 3 assumptions) per post.

Thanks Joe,

Brian Coote

[bojan]

There are two of them:
Eclipse Orchestrator and SET'C
http://www.moonglowtech.com/products/EclipseOrchestrator/index.shtml
http://robertnufer.ch/06_computing/setnc/SETnC_page.htm

I wonder if both of them can run on the same computer... (can't try this here where I am at the moment...)

[bcoote]

I see where Eclipse Orchestrator will run two of some Canon DSLRs simultaneously which is OK if you are running Canon gear.
I could run a ring sequence from the Phottix timer. And the mount is big enough.
Have downloaded both programs and will try them ASAP.
Brian Coote

[Phil Hart]

I am finalising a quote with 'The Moving Group' to freight gear from Melbourne to Cairns for the solar eclipse. So if you have gear you would like shipped to Cairns, please let me know!

A contact has kindly agreed to receive the gear at his work located in North Cairns not far from the airport.

For a telescope, mount, counterweights and a small box of additional gear, I expect the cost to be around $150 each way (ie. $300 total returned to Melbourne). You need to be prepared to contribute a bit more if things don't work out quite as I hope.

Most of your gear should be in sturdy crates to survive the journey and pack efficiently into the truck, but the removalists can wrap up a few things like telescope tripods etc.

Leaving Melbourne on Thursday 25th October, it should all arrive in Cairns on Friday 2nd November or worst case the next delivery on Friday 9th November. Of course, I can't and won't be held responsible for any delays or damage.. you join in at your own risk!

There should be reasonable flexibility with picking up the gear in Cairns.. with hopefully a time available in the afternoon of Saturday 10th or Sunday 11th November. Picking up during business hours either side of the weekend will also be ok. Then everything should be returned during business hours in the day or two after the eclipse.

If you want to join in this scheme, here's what you need to do:

1) Send me an email (via profile link)
2) List exactly what you want shipped, including dimensions and approximate weight
3) Bring the gear to my place in Hawthorn to be ready for collection in the few days before Thursday 25th October

Once I receive your request, I'll reply to arrange payment and a time for dropping off your gear.

cheers
Phil
0438 037 567

[jjjnettie]

My original plan of just using a tripod, the 550D and a 300mm lens just went out the window.
I took delivery of a Polarie + clouds last week.
If the clouds ever disappear, I'm hoping to give it a few practice runs before Cairns.

[bojan]

This applies for EO pro version ($100 !!! ).
I am trying to avoid that cost ... and free version works with one camera only, and it doesn't support serial cable (pro version does, it seems).
SETnC controls one camera only (including 60D.. and scripting is really easy to do).

[bcoote]

So you are wanting to run off an old laptop with a DB9 serial COM1 or whatever socket?
I have an old IBM Thinkpad I could probably cart up there for you.

Have found my Phottix Timer is not any use at all for this. The shortest exposure on a 1 stop change sequence is 0.1 sec

Brian Coote

[bcoote]

[QUOTE=philiphart;899457]Thanks for the offer Phil.
We will be driving to Brisbane and my eldest son will be taking us from there in his 4WD and camper trailer.
Eclipse in 2002 we drove out west of Woomera with C1700 GEM in a trailer with 130mm f8 scope. Found the C1700 was in component parts when we got there and completely unusable. Scope was fine.
Ended up using the Canon D60 with a 400mm Sigma lens on Manfrotto tripod.

Still an unforgettable 20 something sec eclipse.

Thanks, Brian

[OzEclipse]

Brian,

The sequence looks fine and your assumption about short and long exposures for inner outer corona is correct. I edited my previous post to say shoot all shutter speeds in 1 eV increments. If anyone interprets it to shoot every half stop or worse every third stop they'll be there all day. Miloslav Druckmuller even advocates 2eV increments but I prefer 1eV.

My personal preference is not to have a bright glaring live view screen on during totality. So I use live view to focus on the limb through the filter just before totality as I've described then switch it off. My preview function will also be switched off. But if you think you need it on and don't mind the effect on your night vision that's your choice.

Solar Eclipse Ochestrator can only control one camera for the freeware version but Solar Eclipse Maestro can control up to 4 cameras. Maestro is OSx so you'd have to beg or borrow an old Mac Laptop. I have a 2006 Macbook running 10.5 that runs it easily.


Re-14eV dynamic range
The DxO Labs Web Site states : -

"Dynamic range falls rapidly with higher ISO settings, as any analog or digital amplification performed will increase the noise in the darker areas, making it harder to distinguish between fine levels of contrast.

Maximum dynamic range is the greatest possible amplitude between light and dark details a given sensor can record, and is expressed in EVs (exposure values) or f-stops, with each increase of 1 EV (or one stop) corresponding to twice the amount of light.

Dynamic range corresponds to the ratio between the highest brightness a camera can capture (saturation) and the lowest brightness it can capture (typically when noise becomes more important than the signal, i.e., a signal-to-noise ratio below 0 dB).

A value of 12 EV is excellent, with differences below 0.5 EV usually not noticeable."

I know this sounds as though a dynamic range(DR) value of 14eV means you can capture a 14 stop exposure range in one shot. This in turn corresponds to the contrast ratio of the corona.

Pictures on my web site of three total eclipses since 2008 were taken with a 2006 release camera with an 11.6eV DR rating yet they show nothing like an 11 stop DR. A lot of pictures have been taken with 11-12eV cameras like the Canon 5D-same result.

No experienced eclipse photographers I know are abandoning bracketing and shooting single exposures. At 14eV, these new cameras have 2-3 stops less noise and do have more dynamic range than the12eV generation of cameras we've been using since 2007 - Canon 40D, 400D, 5D etc which have ~ 11eV ratings.

This is a welcome improvement but shouldn't abrogate the need for bracketing. I'd recommend you bracket and then see if you can use a single exposure or limited range of exposures to create a masterpiece while having the full bracket set to fall back on.

cheers

Joe
http://joe-cali.com/eclipses

[bojan]

Brian, thanks for the offer, but no need - I have USB-serial adapter that works with DSLR_Shutter on Lenovo lap (w7 home premium) without problems.

However, I would like to drive two cameras from one lap, both via USB (so that I can have a full control of both of them).
Here (in Beijing, where I am at the moment) I have only 60D.. so I can't experiment too much.

It is possible to use DSLR_Shutter (or separate timer) with 60d (and possibly other models) provided camera is placed into exposure bracketing and burst mode. Then, if timer exposure time (actually, this is the time activation signal is active) is set to couple of seconds, the camera will take 3 exposures, with programmed exposure +- bracket.

To cover the full required range of exposures, the camera shutter must be operated manually,which is not good, but if necessary, it is possible.

[Becstar]

I'll just be using my Fuji Finepix S4000 on full 30x zoom with a bit of yellow light solar film blutacked to the lense. I'm on a tight budget so anything fancier is out of reached for me.

It worked beautifully for the Venus transit and I'm hoping it will come out just as well for this eclipse. I'm in Gippsland so the eclipse will be partial only, but I'm still almost jumping out of my skin with excitement about it! :D

I also have some white light mylar solar film that was a fail with the Venus transit as the brightness obscured Venus. But I'm hoping it will be a good tool for the solar eclipse.

[Becstar]

That said, I think I'll die of heartbreak if it clouds over that morning. We had torrential rain and flooding the day and night before the Venus transit and I was convinced I was going to miss it. Yet somehow the clouds parted for me the next morning just long enough to see it for a couple of hours before clouding over again.

[bojan]

Jocelyn from Elysium Apartments says there is a pub across the road ;)

[Peter Ward]

Sounds like an each way bet to me :)

Just have fun.

[bcoote]

Hi Peter,
I thought you thrived on stress.
The stress is at least half the fun.

This will be my last SE and I intend giving it a bit of a shot. if it doesn't work out at least I gave it a try.

Enjoy, Brian

[OzEclipse]

Hi Peter,

Absolutely, it's an each way bet. Basically, I don't think the single exposure will work not matter what the camera specs. So I recommend bracketing - a proven technique. But since Brian will then have a whole lot of single exposures, it can't hurt to see what can be done from a single image. My camera has 14eV DR as well so I'll see what can be done with fewer images. I'm on a boat for next years hybrid. Less exposures sounds good to me :-)

Auto HDR is another possibility but I wouldn't risk my entire eclipse image set on it working properly.

Joe

[DarthWombat]

G'day all...

I am planning to bring pretty much a full astro kit with DSLR up to Trinity Beach: i.e. an ED120 on an HEQ5-Pro. I was planning to set up the DSLR with an intervalometer to take timelapse shots through a white light solar filter during the eclipse.

The question I have is: What I will see in the shots if I leave the filter on through the whole eclipse and not change my exposure settings? Will I still see the shapes of the eclipse in the shots but minus the atmospheric effects? Conventional wisdom seems to be to remove the filter through totality and replace it afterwards to capture the diamond rings, beads, etc, but I am trying to avoid this interactive approach if I can.

One major reason why I am investigating the set-and-forget option is that I will be there with my partner for our first total eclipse, so I don't want to spend the whole eclipse messing with gear and peering at screens. I will be happy to get a nice timelapse sequence without the atmospheric effects while we watch the real thing live through eclipse glasses.

To give you an idea what I am hoping to capture, attached is a sample (boring) solar image taken with my Nikon D5100 through my white light filter:
123918
Will I get a similar result as the moon moves across?

Anyway, I reckon it's all about the experience, which, as I remind myself, may well consist of drinking beer in the dark while whingeing about clouds with other astro people...

Happy to hear your thoughts on this (necessarily compromised) approach.

Thanks,

Alex.

[OzEclipse]

Yes it will work. But what's the point? You could take the picture of the Sun from Canberra you posted and then move a black circle across it in photoshop taking snap shots as you go and save yourself a whole lot of trouble.

I suggest you leave the scope behind and just enjoy the eclipse with your partner especially if it is your first eclipse.

good luck what ever you decide

Joe

[Rob_K]

I bought my daughter a FujiFilm Finepix with the 30x optical zoom and I was gobsmacked with the image quality at 30x. Sounds like a winner! :thumbsup:

Cheers -

[gregbradley]

The cameras with the highest Dynamic Range on the market currently are the Nikon D600, D800 and D4. These are all around 13EV measured by DXO or more like 11.3 measured by others. This is at ISO100 and stays similar to about ISO400. Then it drops off at about 1 EV fall by every doubling of ISO.

5D3 is similar but 2 stops lower in EV to start. The difference is in the shadows where the strength of the Nikons is shadow areas are often fully recoverable with detail and little noise. The 5D3 and D800/D600 DR is about the same from about ISO800 onwards. In highlights the 5D3 and D800/D600 are about the same all the way along the ISO range, its the shadows performance that differs.

I have observed this with my own use of a D800E. It has tremendous ability to recover detail in shadow areas with little noise.
The new D600 is almost exactly the same if not better.

There are graphs comparing the different cameras.

What does that all means?

I think it means you expose to protect the highlights (using Nikon and Canon both) and then with a Nikon you will be able to get more detail out of the shadow (not that I would expect there is a lot on a blackened sun).

If there is a compromise to be made I would suggest losing the dark areas if you had to and keep the highlights intact as much as possible.

With a Nikon it has D-Lighting which can be set to varying strengths. This is what this feature does - it underexposes slightly to protect the highlights.

Some 5D2 users adopt a strategy of overexposing to protect the shadows as 5D2 is good with highlights not so much with shadows. However in an eclipse I am not so sure you want to protect shadows so much as not blow out your highlights rendering the image useless.

I thought that theory may be useful.

Greg.

[bcoote]

Hi Greg
You (and Joe) have shown beyond any question we will have to shoot at 100 or 80 ISO to retain dynamic range.

As far as cameras go it will be a case of stick with what we have for no matter what we have in DSLRs or whatever they are streets ahead of the Canon D60 I used in 2002 which was my only SE so far.

Have nearly finished adapting the plates to mount two scopes and cameras side by side on my EQ6 mount. With two laptops, two scopes, EQ6 with extra counterweights, deep cycle battery, inverter, wooden feet for tripod legs, tools, all the cables and bits and pieces I may have to hire another camel.

Brian

[Matt Wastell]

Good luck all (weather and technical).
I can not make the path of totality but will be imaging the partial from Brisbane (or where the closest clear site will be).
I will be LS60 / DMK51ing for full disc shots - I have already established the shots and layout of my presentation. I may do some 2.5 Powermate if conditions are good - I would love to see some lunar mountains cut across the Sun.
Hope the Sun shines on the 14th!

[doppler]

This will be my first total eclipse, totality only lasts 2 minutes so I will have a camera on my guide scope and a camcorder on a tripod. But I would really like to see a solar prominece through the main scope. Enjoy the eclipse but dont spend too much time trying to image it

[Adelastro1]

My new Polarie arrived today. Woohoo! I've got the weekend now to play around with it before the eclipse.

I'll be using two cameras with different lenses.

For the close up shots I'll use a D7000 to give the extra reach of a DX body and Sigma 50-500 on the new Polarie. Also have a Kenko 2x teleconverter to try it with too.

For the wider shots of the corona I will use my D800E with the Nikon 80-200 f2.8 and possibly a TC-17EII, non tracked.

Also will swap the Nikon 14-24 f2.8 onto the D800E for the partial phases of the eclipse.

Even if it's partly cloudy I'm sure I will get some good shots. That's the idea of keeping it simple and being able to adapt on the day. Plus I can't carry much anyway!

I'm literally in Cairns for 15 hours total so plan to go straight to my site and stay up all night. The flight home is 6 hours so there's plenty of time to sleep then!

All the best everyone and good luck observing/imaging it!

[Davros]

I will be attempting to do some artistic widefield shots from Redcliffe with the Canon and a 28-70L using a combination of ND filters and solar film for different stages. Mostly i will be watching it through my eclipse glasses with my wife by my side.

[gregbradley]

I did some experimenting with the D800E with various lenses. 24-70 with a variable ND filter seemed very good. 180mm F2.8 ED was also good.
77mm Hoya R72 infrared filter also seems useful.

I am wondering if I should just use the D800E on a tripod and doing a time lapse. And shoot with 40D on my 110mm which is a good combo.

Greg.