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Full, FULL spectrum 1000D mod.


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Well I finally did it.

I've had the second (anti alias/ dust) filter removed in my 1000D. With the original "full spectrum - filter removed" mod the remaining filter still acted as a UV-IR cut-off and limited the spectral coverage to 400-700nm.

It now can "see" well below 370nm and right out into the NIR. Excellent for spectroscopy.:)

The only downside, however, is, like the early mods to the 300/350 models, that you loose the ability to focus with standard lenses.:(

I can't find any of my Zuiko or Canon lens which will now focus at infinity.

I suppose the "ultimate" mod would be to remove the #1 filter (Canon colour balance filter) and replace it with a clear glass filter and then remove the #2 completely.....

Onwards and Upwards.

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I've modified both a 450 and 500D bodies with a filter glass from Edmunds Optics (York) which is simply a plain glass with anti reflection coatings to both sides. This will give you a full spectrum (minus whatever UV end the glass removes) and maintain the focal plane position as its thickness is 0.003" different from the original IR cut filter in the above cameras. Cant remember the stock code at the mo but can find it if you think it might help...

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Sounds good.

This would still leave the UV-IR cut-off caused by the #1 filter element, so this would also have to be removed for spectroscopy.

Could solve the standard lens problems.

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Bern (Modern Astronomy) stocks a 1mm thick EOS T adaptor (10mm thinner than the standard adaptor) if this was used (perhaps with a short extension piece) you would be able to get focus with all those "cheap" t mount lenses that are out there...

I made my own a couple of years ago with "focus confirmation"... this reduced the thickness by 5mm and works a treat with the filter removed 350D...

34815d1270830236t-low-profile-eos-t-adaptor-focus-confirmation-low-profile-eos-t-adaptor-focus-confirmation.jpg

http://stargazerslounge.com/diy-astronomer/101245-low-profile-eos-t-adaptor-focus-confirmation.html

Peter...

Edited by Psychobilly
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Peter,

I have one of these. Works OK for the scope and spectroscope, but with say the Zuiko lenses the Oly to EOS adaptor is already only 1.8mm thick and still the lenses won't focus.

Really need a way of allowing the lens mechanism to move the internal elements about 1mm further ie beyond the normal infinity focus.....

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Another thought....

As the combined thickness of the filters is only around 1.6mm (filter#1 + filter#2) the focal shift will only be about 0.5mm

Is it possible that the "clip in" filters can be used BEHIND a standard camera lens - or is there insufficient space for the rear lens element???

(I looked at this for the 300D - no suitable clip in filters and the required thickness was 2.8mm)

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That all depends on how far the rear element of your lens protrudes behind its mounting flange and where the mirror comes to when it lifts. If your using different lenses then you need to know data for all.

I've turned small adapters to fit onto the back element housing of lenses so I can fit my 1.25" filters behind the lens as buying full sized front end filters is too expensive. If you know someone that could turn a small flat faced adapter you could stick the filter to the flat face... just a thought

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Peter,

I have one of these. Works OK for the scope and spectroscope, but with say the Zuiko lenses the Oly to EOS adaptor is already only 1.8mm thick and still the lenses won't focus.

Really need a way of allowing the lens mechanism to move the internal elements about 1mm further ie beyond the normal infinity focus.....

But that's because the OLY/EOS adaptor is correcting the register distance between the two different lens systems... the shortened T isn't :) It does mean that the focus marks on the barrel no longer correspond but thats a small penalty to pay...

Peter...

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[Quote...

Really need a way of allowing the lens mechanism to move the internal elements about 1mm further ie beyond the normal infinity focus.....]

If your feeling brave there's usually a rubber focussing ring around the lens barrel - lift this and you might find a small screw that acts as a stop locator, remove and this allows the focus mechanism to travel beyond its normal distance (I've done this on a couple of lenses where extra travel was needed - at your risk though...)

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The Astronomik MC EOS clip in filter arrived today. Thanks to Bern at Modern Astronomy.

10 sec is all it takes to fit.....

Yes!

Is does work!!

I now have the ability to infinity focus my ol' Zuiko lens on a fully, FULLY spectral modded 1000D....

Just need a clear night to test 100% under the stars - but things look VERY promising.

Onwards and Upwards

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The specs certainly say it would bring the colour balance back to "normal"

BUT it's only 1mm thick, so for any mod ( pre 450D model) which involved the removal only of the original Canon filter - this would not restore focus. On later models with only the #2 filter removed, yes focus would be OK

HTH

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As they say, I can't win 'em all. Perhaps I should have fitted an Edmunds glass filter while I was there. But I didn't.

Didn't know the 1000D had two filters. What does each do? (Excuse total ignorance).

After successfully completing the mod of my 350D yesterday, I ordered a 2" Baader UV/IR cut filter from FLO.

From the above, it appears that you guys have no qualms in going back and repeating the exercise of camera strip. Is the 1000D more amenable to strip down to the filters than the 350D series.

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Howdie, did you remove just the both sets of glass? Reason I ask is that I have already modded my 1000d but have found that there is a scratch on the dust/piezo glass and was wondering if you could simply remove this or the whole fitting and still use the camera as normal?

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I haven't done this mod myself so I can't comment on degrees of difficulty....

In the Canon 450d (and on all later models) they reduced the thickness of the colour balance uv-ir filter (filter #1) and added a new filter (filter #2) - an anti-alias/ dust shaker filter to the front of it. Unfortunately for me this filter #2 also acts as a UV-IR cut-off filter.

With both filters removed you get full (FULL) spectral coverage but loose the ability to focus standard lenses...this appears to be corrected by using an Astronomik EOS clip in filter. I used the MC (clear) version, but others have suggested the OWB (white balance filter). I can (i hope) still use the camera for family shots by defining a Custom White Balance correction in the camera.

HTH

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What I don't understand is why DSLR manufacturers don't see a business opportunity here. What we astronomers really need is a DSLR will all the DSLR bits removed. We don't need a mirror, a finder, filters on the sensor and so on. Surely leaving all these bit out would mean it could be manufactured cheaper. Sell it for the same price as the equivalent DSLR model. They would make money and we wouldn't have the risk of opening it up and removing the filters. Also, there would be no vibration from the mirror flip. And it would still be way cheaper than those dedicated astro CCDs. (Although, technically, it would then be a dedicated astro CCD).

end of rant :)

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I think it just comes done to the commercial realities of making and selling "consumer" cameras to the masses.

Canon tried it - once - with the 20Da, never again!

To mod the camera for astro work would not be done at source...the total number required to saturate the astronomy market is insignificant compared with the thousands of "standard" cameras sold world wide.

Such is life!

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Yes, that's the problem alright :( I get it all the time for many things - market too small. So need to modify something that IS available! That's economics for you :)

A dedicated DSLR type sensor is what I could do with too. I was wondering about buying a cheaper camera to modify. Don't need all the bells and whistles of an expensive DSLR. Anyone have any thought on this? A sensitive and fairly high res image sensor is what we require I think, I for one, could make up the mechanical bits to mount it on the scope. So it doesn't even need to be a camera with interchangeable lenses and TTL viewing and metering. I guess a shutter may be helpful but a direct video feed from the image sensor would be fine instead.

I should add... a large sensor is wanted for wide(ish) angle views.

Edited by Gina
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Gina, the problem is that the cheaper compact cameras all have a tiny sensor area.

But I see where you are coming from, Merlin. If the numbers would add up, I guess one of the manufacturers would have done it already.

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