Finally got myself a Canon 400D

[Astroman]

YAY :party:

Finally got the camera and a 2gb CF :)

now to image :)

[acropolite]

Congratulations Andrew, the comet is still quite visible BTW, don't do what I did and forget to take darks, I used in camera long exposure mode which automatically subtracts darks but the raw is not subject to that and very noisy without a dark frame.:camera:

[g__day]

Hey Andrew - me too about 2 weeks ago, suggestion get an external DC adapter if you plan to image long term somewhere nears main power - about $100 if you shop around.

Right now I've downloaded the 30 day trial versions of MaximDL, MaxDSLR, DSLR Focus and DSLR Shutter and am busying reading manuals!

I understand for long duration photography you have to enable the Bulb function, which it seems you can't do in any software operating via the supplied USB cable????? (serious software design oversight there). So I am busy waithing for a ShoeString DUSB USB shutter cable to arrive - as I have read in online forums that most software seems to work with that.

I say most and not all because I hear the renown DSLR Focus doesn't, even though it specifically supports the 5D, 20D, 300D and 350D! I've written to Chris twice now asking if there is a workaround or any idea when a release may add support for the 400D - no reply in over 10 days...

I'd be curious to know what settings you use for photography. So far I have tended to use the supplied Canon EOS utility with the camera directly attached to a scope and the control wheel set to Av settings, set ISO to 800 or 1600, and take 30 second snaps for nebula, down to 4-5 seconds for bright planets like Saturn. I set the Bias is it to +2 - it gives the best results for the faint dust in nebulae.

My shots seem to have a green tinge to them, for instance M42 below, which I understand should look pinkish (after photshop?). So I guess you need to adjust the RGB settings of the camera to give more priority to certain colours. I have yet to play around with dark frames - but once I exceed 30 second shots that is a must do.

The camera seems to have plenty of quality, its just learning curve I face now!

Happy to swap learnings on this one buddy!

[Astroman]

All I did with my test images http://www.iceinspace.com.au/forum/showthread.php?t=17517

was to have the camera on the mount directly, no scope, with the 200mm lens. The cameras settings were 30 seconds in manual mode F5.4 (the smallest amount the lens would goto at 200mm) and had the timer on. so I clicked waited then exposed, then waited for the noise reduction to stop then looked... In the settings you have to turn on the long exposure noise reduction. I also shot in RAW.

[Marc]

Hi all,
I also just bought a 400D. Awsome! I tried my first astro pic on McNaught. I set shutter priority, ISO 800 and compensation to +2, which was probably a bad Idea, as i got a lot of noise, even with noise reduction on. I popped it piggy back on my 8" Newt and set a 10 second exposure. The image was RAW.
I've also got a remote shutter release on order as well.

A couple of q's, though;

How do you focus without any realtime LCD display? I found the experience a bit daunting, as I really want to get into deepsky imaging.

Second question;

What are dark frames? That's something I've not heard of.

Anyhoo, here are the results of my first foray into the world of 400D!

http://img408.imageshack.us/img408/1449/cometmcnaughtc2006p19nu.jpg

Cheers

[mnm]

Hi all,
I also got a 400D last week, I haven't tried it on the scope yet. I've just been taking terestrial shots at the moment figuring out all the options, lots of stuff to learn, but it takes great pictures. I'm making my own serial cable, then probably buy a USB to serial adapter to use with it later.

Martin

[g__day]

Marc - you focus roughly on a very bright star - like Sirius - using the LCD, then via a PC hook-up I guess, take a shot, adjust and repeat until your focus is great - then away you going imaging.

I believe a dark frame is a shot with the lens on - so any bright bits are likely to be permanent electronic noise you can subtract out of all your real shots.

[Marc]

thanks for the update, but the 400D doesn't allow realtime update (ie focusing) via the LCD - it's just for settings and playback. if there is a custom setting that I have yet to discover that would be great!:) I think I'm going to have to get an off-axis guider...(can you get those for Newts?)



So what you do is take a shot with the lens cap on, and subtract any values above RGB=0 from further shot in post processing, is that how it goes? I heard that you can determine the signal to noise ratio by doing this, but I thought that was it.

[mnm]

Use a program called DSLRFocus, it takes images from the camera in realtime and compares them to either autofocus or help you manually focus depending on your setup. It also does a lot of other stuff, read all about it here: http://www.dslrfocus.com/

Martin

[iceman]

Rather than take dark frames, some people just use the in-camera noise reduction, which does a remarkably good job.

Bert (avandonk) has done a lot of testing in this area (dark frames vs ICNR) and swears by ICNR.

[g__day]

I guess you can do both (dark frame and in-camera noise reduction.

Interestingly reading a book on astro-photography last week (Rod Woz) it said if you are doing a 3 minute capture, spend the same amount of time doing darks (for each and every shot you do) plus flats and bias... I guess that is to push the equipment as far as it can go. The longer your shot - the more noise you are exposed to so the longer your darkframe should be to replicate exactly that same electronic function.

Bias I presume is adjustment for the CCDs over or under emphasis of Red, Blue and Green (more reading yet to do). I presume flats are to address off axis error (where stars in the centre of view are lovely little circles, but stars towards the edge are less focused football shapes (unless you own an expensive APO or true RC type tube.

All this assumes you will import your shots into MaximDL or CS Photoshop etc to process the raw information and darks / flats / bias.

Marc the other part of your question on achieving critical focus - and everyone says over do it, and adjust as the night progress and your gear is subject to thermal expansion or contraction and/or mirror flop. I focus on say Sirus - roughly thru the view finder, then snap 5 - 10 second exposure checking the focus until its as good as I can get. DSLR Focus can likely help this by checking and minimising the size of a designate star/s - meaning you have obtained optimal focus.

This done its onto the main game and longer duration astrophotography. I had my first play last night - scopes both aligned, focus good, bulb functioned worked - and I did 10 seconds, 30 seconds, 60 seconds, 2, 2 and 4 minute shots (guided) until yep - the clouds all rolled in!

Post what I got a bit later on tonight.

[gary]

Hi Martin,

According to the DSLRFocus web site, the 400D is not supported at this time.

Best Regards

Gary

[merlin8r]

From memory, when photographing in RAW format (which gives you full 12 bit data), the camera doesn't do noise reduction. But don't quote me on that, I just seem to remember reading that somewhere in the manual.
I found the easiest way to take darks was just put the cap back on the telescope. Remember to pause for a couple of minutes after your luminace frame, to allow the chip to cool back down.
Dark subtraction is very easy in Photoshop. You just open the 2 frames (1 image and 1 dark), move the dark over the image, and select "difference" from the application menu on the right. I don't have it running here at work so I can't give precise instructions, but it is very easy. I haven't got onto bias frames yet.
My Ultrawedge just came in, so at last I can start with some longer frames this weekend w00t!!!

Clear skies,
Shane

[iceman]

That's not correct. It will always do noise reduction if:
1) You have it set (in custom functions menu)
2) Your exposure is over 30 seconds.

[Marc]

Been to the site, and found that DSLRFocus doesn't upport the 400D yet - Bugger!:(

EDIT: Sorry, Gary already made the point. Still a bugger though...

The up-side is I got my RS-60E3 Remote release yesterday.

[Astroman]

I gotone the other day too Marc, handy little device, dont like the idea of using an IR trigger when you have to get INFRONT of the camera

[merlin8r]

Ahh thanks for that Mike. I only just got the thing. I don't remember where I heard that. Do you think the auto noise reduction is as good as manual dark frame subtraction? Would be a lot easier if it was!

Clear skies,
Shane

[g__day]

Well interestingly I have taken a few shots this evening - ranging from 90 - 240 seconds - M42, M46, Eta Carina and Omega Cluster - and taken a few darks, two interesting observations with noise reduction switched on.

1. Darks are nearly pitch black - I see no discernible noise whatsoever

2. The bulb shot for say 120 seconds, processes for maybe 120 seconds after the lens closes before the image is composited to the LCD / PC - maybe it is doing appropriately framed darks by popping up its prism, taking a dark, then subtracting it from the last image?

Pretty smart if it was!

PS

Had to add this time to DSLR Shutter to ensure a sequence isn't chopped allowing for post image processing by the camera.

[Astroman]

The cameras noise reduction (dark frame subtraction) takes an image for the same length of time as the image you just captured, so if you took an image of 120sec the camera will do a noise reduction for the same length of time, 120sec. Nothing moves inside the camera when the dark frame is being done it just simply captures an image whilst the shutter is closed (same as having a lens cap on) Then processes the images before writting the file (.CR2 and/or JPG). Best just to leave the camera alone during this process to prevent any missread information onto the CF card.

Hope this helps a bit..

Havent had a chance to try a few deeper exposures around Orion etc... have to waitfor the weather to clear up, but I am having fun learning about Deepsky Stacker, a neat little program that stacks quite well, both my scorpio and Orion shots were done with it... Lacks a bit of editing power, but thats what Photoshop was invented for :)

Oh Photoshop CS3 comes out in March.

Does DSLR shutter work on the 400D then? How do you connect from the DSLR to the program, will the supplied USB cable work?

[74tuc]

Hello Andrew,

Just looked at your pic.

What lens did you use to take this pic?

What exposure ?

What tracking (if any)?

There may be a problem here.

Jerry.:)

[Astroman]

which pic?

The Scorpio one is a stack of 6 x 15second images taken with an 18-55mm kit lens sitting on a tripod (no tracking)

The Orion image is 2 x 75sec Tracking using an EQ6 (not properly aligned) 80-200mm lens

Cant remember the ISO settings would have been around 400, will have to check the CR2 Exif data...

Whats the problem?

[74tuc]

The pic that I am looking at is M42_small.jpg.

What I see is types of 2 aberration (excessive shperical and chromatic) and if I am correct I would take the lens back to the seller and demand an exchange under warrenty.

The focus point seems to be half way between Phi(1,2,3,)-Ori and M42. The star near this centre there seems reasonable round. Please observe the distortions around this point and you will see what looks like a comatic blurr that extends radially and with increasing chromatic aberration. Perhaps this is field distortion.

Take a couple of test wide angle terrestrial pics of straight objects and examine the pics.

Jerry.:)

[Rigel003]

Answers to all of the issues in this thread are thoroughly and sensibly addressed by Jerry Lodriguss in his ebook "A Guide to Astrophotography with Digital SLR Cameras" Highly recommended.

http://www.astropix.com/GADC/GADC.HTM

In camera noise reduction does its own darks of the same length as the light frames and subtracts them automatically. You shouldn't use this as well as subtracting your own darks. In general if you want the best results and are combining lots of frames, shoot raw and do your own darks - it gives you better control of the calibration process afterwards, and it's a more efficient use of exposure time.

If you are shooting easy subjects using single frames or a just a few combined and not planning any post processing calibration techniques, then the in camera noise reduction is definitely worth using.

[g__day]

Andrew -

DSLR Shutter is working from PC's USB cable into a ShoeString Astronomy DSUSB converter (around AUD $90) with a three pin 3.5mm jack output that is stepped down into a 2.5 mm three prong jack that goes directly into the camera's Bulb function socket above the USB slot on the camera. DSLR shutter sees the Camera only via the Bulb cable. The Canon EOS control software see the camera, and that its in Bulb mode, but it can't send an open/close command to it!

The Canon 400D can be put into Manual + Bulb using the two dials on the camera, and their software recognises this - but it can't send a Bulb command along that same USB cable for some unknown design rationale - the camera appears to be limited / designed into only accepting bulb commands on the bulb in port - sigh, I wish it worked on either port!

Here is what I consider the best shot of the evening / morning, from light drenched North Ryde, a 2.5 minute shot of Omega Cluster at ISO 800, which I then imported into MaximDL and riased the Histogram's white cut-off from 23 to 33 to darken the background sky more. Then I took this good looking output and imported it into SmartSaver Pro and turned it from a JPEG to a recursive JPEG to shrink it from 4mb down to 900k. I did this again and shrunk it to a 14% quality to fit it to under 150k to post it here. Visually I think its my first "real" shot that I'm still proud of this morning!

I think I can step up and say finally, I'm an amateur astro-photographer now - with alot to learn!

I am amazed that the C9.25 CF XLT + Meg 80mm piggy back on a CG-5 - loading it to probably just over 15kgs - its absolute maximum - has performed this well. I'd much rather have a real mount (Tak, G11, Atlux, CGE) but this little beaut has done me proud last night. And all my gotos where almost spot on the centre of the CCDs of the Canon and Meade DSI chips! A perfect night just about, and the astrolab kept all the dew right off till I packed it in at 3:30am.

Finally to add to my pleasure MyAstro had sent me a Vixen 13mm LVW eyepiece that I used on Saturn and Omega - blew me away how good this was, Omega leaped out at me - in moderately poor viewing skies, and Saturn was easy to see the Cassini division and the cloud bands of Saturn.

Score 10 out of 10 for satisfaction recieved last night!

[Astroman]

Hi Jerry...

This was taken with a cheap 80-200mm lens I picked up cheaply, so wasnt expecting perfect results with it. it will do me until I get the adapters etc to hook up the camera to the scope.

[74tuc]

OK Andrew.

You have an excellent camera. To do it justice you need very good lens.

Jerry.:)

[iceman]

g__day, great shot! To look better for the forum, you should reduce it to 800px (or so) wide BEFORE saving as jpeg. That way you won't compress it so much to get it under 150k, and the whole image will look tighter and better!

[g__day]

Thanks Mike,

I was going to ask that question shortly. Can you please spell out in a bit more process how this is done please?

I have been taking shots as jpegs (rather than raws) and using Smartsaver Pro to turn them into recursive jpegs (at 75% quality 4mb squishes down to around 600 - 800 kb) with no apparent quality loss. But shrinking these down to 15% quality to hit 150kb does kill the image quality.

Can you spell out the steps from capture to compression for me and what software you suggest to do it and I will give it a whirl!

Meanwhile - M42 - overbright (given the high dynamic range witihin the shot) and I'm playing with Photoshop and MaximDL - just to see what they can do without reading the manual) - upon compression here's my 2 minute shot.

[Marc]

Woe is me! :sadeyes: Seems I've got a lot of s/w and equipment to get before I can start getting the results you have, g_day. I've had a look at the Diffraction limited site and although very good, their software is a bit beyond reach at the moment (since I bought the 400D!) I know you can get a demo (already done that) but by the time I've ordered the cables/adapters et al, and fluffed around a bit, my trial will be up!
However, I will persevere. I want to move on from being an Astronoob to an Amateur Astrophotographer!:D

[RB]

I wouldn't say that.
What equipment do you have Marc.
You don't need lots of software, and high end equipment to get results.
If you learn the basics, you can do adjustments with most imaging software although I'd highly recommend Photoshop as your main imaging software until you get a good understanding of the principals of astro imaging.

You can mount your 400D on a tracking EQ mount and use your camera lens to start off with. This would give you an idea of the in's and out's of astro imaging before you jump in the deep end.

[Marc]

Rocket Boy,

What I do have is the 400D, an 8" Newt (Celestron G8N, short) on EQ5, with dual axis drives (not goto), X-Cel 5mm, 32mm Nexstar and stock 20mm plossl, Omni 2X Barlow, Thousand Oaks OxyIII, Celestron Polarising kit & Neutral density filter (25%). You could say I'm a fan of the Orange and Black!
I have been doing a bit of regular DS observing, not astrophoto, for the last 4 or 5 years. I bought the G8N with the view (boom! boom!:lol: ) to do a bit of Astro-photo in the future.
My ideal setup is to have a solar powered roll-top observatory with a concrete pier mount.

All in due time of course. I am pretty sure the cosmos will still be there when I get my act together.:thumbsup:

[RB]

Great !

You don't really need goto, to get started.
Mount your 400D on the scope, use a wide-ish lens, say 50mm and do some piggyback imaging first.
You'll learn a lot from piggyback imaging that will prepare you for prime imaging when you get you observatory underway.