To Mod Or Not To Mod...

[dugnsuz]

...that is the question. Whether 'tis nobler in the mind to suffer the slings and arrows of outrageously low H-alpha response, or to take arms and MOD!!!!

That Bill Shakespeare was ahead of his time eh!??

Mod fever seems to have well and truly hit IISers.
I'm still a fence-sitter at present.
The idea seems fine, but here I invite modders and moddees to tell us potential wanabees(!) if it's all worth the hype.

A lot of us will be using the 'family' DSLR to do Astro work and daytime photography. Can a custom white balance or filter reproduce the quality of the pre-modded camera? Some examples I've seen online don't look too good (scroll down a wee bit)...
http://ghonis2.ho8.com/rebelmod.html

Are the resulting images that come out of the camera easier to process - what's the difference? Dramatic, Subtle???

Are exposure times significantly reduced?

Is there a risk of over-saturation on lengthy subs?

Would it be just as worthwhile leaving the DSLR alone and using a good quality Light pollution Filter to push the length of my subs a bit more?

Lots of questions - I don't expect them all to be answered, but some user experiences might be really helpful to us on the edge of nirvana/oblivion!

Cheers all

Doug:thumbsup::thumbsup:

[leon]

Doug you forgot to put, who wants to mad their DSLR, but is to chicken, :whistle: so at this stage cant put a tick to any of the options, other than that it will be an interesting result.

Leon :thumbsup:

[Zuts]

Hi Doug

Just my 2 cents, but if you dont mod it then you will never get a decent Ha response as the cutoff is above the Ha spectrum. So i may be wrong but no matter how many subs you take you will never get all that lovely Ha structure as the filter rejects it; and your Tarantulas will always be blue.

If you are happy with that then no problem because obviously looking at your work you can get some lovely photos. IMHO it's always best if possible to go the dedicated route and pick up another DSLR for daytime stuff. The filter you stick on the front of a modded DSLR to get the white balance back is 25% of the cost of a 400D body anyway.

Paul

[Ian Robinson]

Maybe the following Canon EOS Insert Filters ( http://www.telescope-service.de/filters/start/filtersstart.html#EOS_Klemmhalter ) might be a better option than the Baader style front filter change overs for DSLRs that involve pulling the DSLR apart and which radically change the colour response of the DSLR when used for happy snaps and NORMAL photography ?

.... when I get my 40D I just don't want to go there .... and will take a lot of convincing unless Telescope-Service come up with a AS EOS Korr that suits a 40D.

If I do a mod , I will be sending tbe body to Baader to get the job done PROPERLY !!! That's a big IF. I don't want a $1500 camera stuffed up by an incompetent camera mechanic or my warantee voided.
See below for what's involved with a 350D , I imagine similar for a 40D.
http://www.astrosurf.org/buil/350d/350d.htm

and Baader's information on this process http://www.baader-planetarium.de/download/filterumbau_canon_dslr_e.pdf is not cheap , 395 Euros + insured traceable postage both ways.

The filter transmission curves here http://www.astrosurf.org/buil/filters/curves.htm#Badder%20UV/IR are interesting , I am looking for the curve for the standard canon 40D front filter (anyone seen one somewhere ?)

If the 40D front filter transmission curve the same as the 350D (or 400D) curve (which passes 25% of Halpha that falls on it , so matched up with a Lumicon Deep Sky Filter or a Lumicon Halpha Pass Filter (and longer exposures ((2x longer), or a suitably higher chip speed setting (2x higher ISO) because only 1/4 the Halpha is getting though the standard canon front filter) will still give a nice response in deep sky photos - I would think.) see graph for standard 400D filter and Baader filter.
http://www.telescope-service.com/baaderpics/accessories/ACFFilterCanonFilter.gif

Halpha band is very narrow .

My 40D will be used not just for astro imaging.

At this stage I am leaning more towards a 2" Lumicon Halpha or 2" Lumicon DEEP SKY which will be cheaper and I can attach it to the front of my coma corrector , so I can use them with my Minolta 35mm SLR too , and later if I decide to go there later on , with a dedicated CCD imager (one of those SBIG or similar jobs) as well , and I suspect will be just as good at bringing out those nice red gas clouds.

[Matty P]

I intend to mod my DSLR in future but I am in no rush. The prospect of having modded DSLR camera that can produce some breath taking DSO images is any amateur astrophotographers dream (mine anyway...).

I've seen some amazing images taken with and without a modded DSLR and know the difference a modded camera can make. But at the moment I am quite happy if my Tarantula's are green.

If I was going to get serious about astrophotgraphy, I would do what Paul suggested and get two DSLR cameras. One for general daytime use and one for Astrophotography. That way you don't have to worry of colour balance etc.

I guess I am lucky that I haven't caught the modded DSLR camera fever yet. :lol:

[Terry B]

No, I will leave my 40D unmodded. It has a little response at HA frequency so isn't totally blind and is much more useable during daytime as is. If I had the money I would get a QHY6 for colour astro imaging and save the mod headache.

[skwinty]

I had my 40D modded by hutech.Sure there was a US$600 price tag.
however, I am happy with the results:):):) and the custom white balance for jpg daylight photography works very well. I make sure that I use a CWB that matches the light conditions, so I suppose the downside is having to make a CWB for every different light condition. I use a piece of white paper which I keep in the camera bag. I could also forego the CWB and use AWB and fix later in Corel Photopaint which came with the camera.
Of course when shooting RAW none of this applies.:thumbsup:

[Alchemy]

At this stage im the only modded voter, and being that i am happy with the results produced , the real benefit is in the Ha objects ie helix, horsehead, as these are a dead loss with a standard camera, however for galaxies the standard is just as good..... a modded dslr is a great way to get into the deeper Ha objects, and can be picked up 2nd hand for less than 1000 dollars. the qhy8 is the next level at a lot more money. if youre uncertain with those higher end 40d cameras buy another older one just for imaging Ha.

[Ian Robinson]

25% transmission of Halpha is not that bad , it is a very narrow band. See my other post.

[Omaroo]

I'd never use my new 350D as a terrestrial camera -I've got my Nikons for that.

I will, however, be modding my 350D with the Baader ACF filter as soon as I've done a couple of disciplined sessions with it first to take some "control" shots under control conditions.

I'll then do the mod and repeat the conditions above. I'm looking forward to seeing the real difference.

[Bassnut]

Sheesh, cause the mod is worth it. Risk is part of the fun, or be forever fustrated with sub-standard imaging.

[EzyStyles]

you already know what im going or have voted for :) . Doug, seriously, some people think it doesn't make that much difference between a modded and a non-modded DSLR but they have never used a modded one before. You'll need to ask the ones who have used a modded and a non modded and i can gurantee you, they never regret getting their DSLR modded.

You certainly can use a modded DSLR for daylight use. See for comparison under FAQ.

http://www.ezystyles.com.au/modification.html

;)

To make the 40D perfect for normal daylight use (literally identical to an unmodded version) you will need the Daylight Front Filter. After using correct white balancing on a modded DSLR, colours will still be slightly off only slightly. With a daylight front filter, this will correct it back to normal. The only drawback is that you cannot use EF-S lense as the EF-S lense will hit the front filter.

Once you have your 40D modded with a UV/IR filter or clear glass adding a daylight front filter:

Advantages:
- Can be used for astrophotography
- Can be used for daytime photography
- All automatic dial functions work perfectly
- No need for custom white balancing, can leave it in AWB
- Clear glass version can be used for Infrared Photogtaphy

Disadvantages:
- Cannot use EF-S lense.

In regards to exposure time, definitely a modded DSLR requires much much much less exposure time to get the same amount of photon's than an unmodded DSLR.

There will be a risk of over-exposed images with lengthy subs whether if it is modded or unmodded.

cheers.

[Zuts]

Hi,

I am not sure if i am reading the graph correctly but the following suggests that an unmodded 40D has a much worse response to Ha than an unmodded 350D.

Less than 10% Ha is let through? If this is true then its like shooting at F50 for Ha so I would agree with bassnut and say mod it.

http://www.astrosurf.org/buil/eos40d2/filter.htm

Paul

Edit.. Actually the graph is relative response but i still reckon mod it :)

[Terry B]

The graph demonstrates that the unmodded 40d is worse than a modded 350d as expected. The modded versions are essentially equal.

[Ian Robinson]

Babel Fished the website , makes for interesting reading . http://babelfish.yahoo.com/translate_url?doit=done&tt=url&intl=1&fr=bf-home&trurl=http%3A%2F%2Fwww.astrosurf.or g%2Fbuil%2Feos40d2%2Ffilter.htm&lp=fr_en&btnTrUrl=Translate
-a longer exposure would bring out more nebulosity on the unmodded 40D in fig13.

I'll hold of for a while I think when I get my 40D.

[dugnsuz]

Well thanks all,
...a very interesting start!
:thumbsup:

[dugnsuz]

Cheers Paul...agreed, if I dont mod I dont get the Ha response I want, simple as that!
:thumbsup:

[dugnsuz]

How so Steve?
Does this mean if I shoot my happy snaps in RAW format there would be no need for a CWB of filter?
Doug:thumbsup:

ps... found an explanation!

Raw files have not had while balance set. They are tagged with whatever the camera's setting was, (either that which was manually set or via auto-white-balance), but the actual data has not been changed. This allows one to set any colour temperature and white balance one wishes after the fact with no image degradation. It should be understood that once the file has been converted from the linear space and has had a gamma curve applied (such as in a JPG) white balance can no longer be properly done.

[dugnsuz]

Downloaded a modded daytime pic from Peter Tan's website (he was using it to demonstrate that a DSLR he has for sale produces suitably red results I think)

Did a real rough play about with Windows Picture Viewer to try and get a half decent white balance - pretty easy, not the drama I had thought it might be!
Doug

[RB]

Doug, that's a good summation of RAW file WB, that's why shooting in RAW is a big advantage for terrestrial (if you take a small amount of shots), if you do a big run it gets time consuming so I shoot in both RAW and jpg, so I can go through and edit all the good RAWs and keep the rest as jpgs too.
Of course you still need to have your settings well reasonably adjusted because RAW is not a silver bullet.
In astro using RAW gives you better latitude in bringing out finer detail because of the bigger dynamic range you have to play with.

I had a go at adjusting the WB in CS2 of the image you posted too.
It's amazing the hidden detail even in such a small jpg file.

In CS3 you can do a batch WB conversion on a bunch of images with similar conditions such as similar outdoor shots by opening all the images you want to adjust, then doing the WB conversion as in this example, then dragging the adjustment layer on to each individual image.
The correction you applied to the first will subsequently be applied to the rest.
Makes it quiet straight forward to use a modded camera then for terrestrial shots too.

[dugnsuz]

thanks Andrew - that redo looks much better. I didn't have access to PS to try it out.:thumbsup:

[Craig_L]

Forgive me if I've got this wrong, but if filter 1 on the 40D is a UV/IR filter with similar response to a Baader UV/IR (maybe a little more IR), what is wrong with modding the 40D by just removing the IR cut filter - filter 2, apart from the focus problem by not having the extra thickness of glass, and if you are not intending it for daylight use as well? I was thinking of doing this with the 400D which I assume has the same filter 1 and 2 as the 40D.

Any thoughts?

Craig

[Terry B]

This is exactly what Christian Buil states in his write up at http://www.astrosurf.org/buil/eos40d2/filter.htm
(put it into Babelfish for a reasonably readable version)

[Craig_L]

Ah, I see it now Terry. My French is not good. Thanks.

Has anyone on the forum tried this I wonder?

Craig

[Ric]

I still have way too much to learn in general before I start thinking about modding my 400D.

Cheers

[ZeroID]

My new SONY A77 has arrived, I won't be modding that BUT I will take a look at my KM Dynax 7D and have a go at that. It won't get used photographically again. The A77 will do dual use though, Terrestial and astro. It's very sensitive and at 24mp should get something useful.

[swannies1983]

That's exactly what I did. I had been imaging with my Canon 400D for a year but picked up a modded 30D through IIS about 7 months ago. Only had a few sessions with the 30D but have been impressed with what it can pick up.