Lenses for filter removed 300D?

[haitch]

Just wondering if anyone has experience of succesfully using EF lenses with a filter removed EOS (earlier ones with a single filter not the later models where you can leave the other filter in place).

I don't mean L lenses, I know they mostly go far enough past infinity to still focus after the mod but my wife thinks my hobby is too expensive already. Just maybe suggestions of a couple of the mid range metal mount ones that'll work?

Cheers

[haitch]

Sorry, also meant to ask if I might have more luck with any if I'm using a clip filter? (I was thinking of getting one anyhow and that would push it up my wish list)

[Psychobilly]

Just wondering if anyone has experience of succesfully using EF lenses with a filter removed EOS (earlier ones with a single filter not the later models where you can leave the other filter in place).

I don't mean L lenses, I know they mostly go far enough past infinity to still focus after the mod but my wife thinks my hobby is too expensive already. Just maybe suggestions of a couple of the mid range metal mount ones that'll work?

Cheers

I have a filter removed 350D like the 300D this also had a single fairly thick glass filter and as such wouldn't reach infinity focus with the standard (cheaper) EF or EF-S lenses..

A mate whos an pro tog let me try a range of much more expensive L series lenses and these would reach focus as most of them have a considerable ammount of travel beyond infinty focus...So I started to buy into "L's" and moved my general togging fron Nikon to Canon...

Some of the older manual focus lenses will allow you to adjust the infinty stop and others have shims between the lens bidy and the mount so you can tweak them to get closer to or maybe even achieve infinty focus...

If you modified the cam yourself and want to use it for lens based work I would seriously consider fitting a clear glass replacement filter infront of the sensor...

It's also worth remembering that the lenses will not bring the IR and UV parts of the spectrum to the same focus as the visible so you would suffer from bloated stars...A clip in filter will help with this and get you closer to acheiving infinty focus but the glass in them tends to be thinner than the filter that was removed from infront of the sensor...

Peter...

[haitch]

Thanks PBS. I've got an unmodded 10D for daytime. The 300D was a cheap impulse purchase with the filter already removed and probably isn't worth the effort of installing a clear glass filter. I'm about to get my hands on an ED80 so that'll probably be what I'll mainly use with it but I was just wondering if there were any lenses I'd get away with for a wider field. That then, knowing I'm going to need an IR/UV filter, lent me towards whether to get a clip filter or a 2". The 10D won't take clip filters so it could only be used with the 300D but if it helped with infinity focus it would be more tempting. Obviously the clip also won't be any good if ever I go down the CCD route (this from someone who promised themself they would never get into imaging!)

[Psychobilly]

One thing you could try is T mount lenses but with the thinner "custom" EOS T adaptors that you can get (Bern ant MA used to sell them the low profile EOS one is 10 mm thinner than the standard one...) ...

http://www.modernast....html#accTRings

The Standard T adaptors are different thicknesses depending on the target lens mount to adjust for the different "register" used by different camera manufacturers...

Thius is the list i usually use for reference..

http://www.graphics.cornell.edu/~westin/misc/mounts-by-register.html

Going to a thinnner adaptor would mean that infinity focus would be achieved a long way before the infinity mark on the lens... if its too short you could use T-spacers to get in in the right ball park... around 5-7mm would put you in the right sort of ballpark

Peter...

[haitch]

Thanks Peter, that's a big help. I was wondering that sort of thing might be the solution.

So if I work on the principal that the EOS register is 44mm + 3mm for the glass lost + 1mm for the thin adaptor plus whatever the specific lens mount is needs to be less than the register of the camera the lens is meant for then I can reach infinity?

[Gina]

I use a Canon EOS camera (1100D) with Astronomik CLS CCD clip filter and Pentax/Praktica M42/1 thread mount lenses and the thinner type "Infinity focus guananteed" adapter and find I get can focus on all the lenses I have of this type. Tightest is the Asahi SMC Takumar 200mm f4 telephoto lens which reaches focus right at the limit but this lens can be dismantled slightly and the infinity focus stop adjusted.

[Psychobilly]

The older cameras had a one piece "thicker" filter so the effect of removal is that much greater than just removing one part of the multi-part in the newer camera...

I seem to recall that the focus point moves by about 1/3rd of the thickness of the glass not it's total thickness..

Peter...