Inukim

Yes, they are different.  Both use 4 optical elements in 4 groups, but the shapes are different.  You are also right in that it's focusing helicoid is longer.  It takes 1 1/2 full rotations from ...

The screw driver set is nice.  It is not exactly standard  JIS, but a special cut made for both phillips and JIS.  While I never tried the set on phillips screws, it fit perfectly in JIS screws. I ...

I have actually already seen that video.  Very interesting.  The finish looks good.

Thank you.  It was a interesting read.

Unfortunately I am not brave enough to try and also don't have another lens with the same issue.  Thank you.

That sounds like it might work.  I will have to give it a try.  Thanks again.

K&F Concept is considered the balance between quality and price.  I have had no issues with them.  If you want high end, Rayqual is the answer.  They have flocked baffles inside some models for ...

Thank you for your reply.  I will look into it.  I do have some India Ink that may match.  It is just that the engravings are very deep into the metal.

As most of you know, a long time ago it was common for owners to engrave the lenses with their name and / or social security numbers (It's probably not a good idea anymore).  I know that they ...

Newly acquired lens. Vivitar 135mm F2.8 Telephoto Close Focusing lens.  I got lucky at a charity shop and got it for less than the price of the generic adapter it is mounted to.  Taken with Canon ...

Thank you.  Good to know.

Thanks everyone for the replies.  I will get a copy for my Eos-7.

How is the image quality of the EF 40mm F2.8 STM lens on a film SLR?  Obviously there is no in camera correction on film SLR's so I was wondering how the IQ is like corner sharpness and vignette.  ...

The EOS-7 and later the EOS-7s had 15% faster eye movement detection compared to the EOS-3 (according to Canon), but with less focus points (7), but covers a larger area of the frame.
The EOS-7s...

Thank you everyone for your help.  I am not too concerned about brand/quality issues.  I am just really curious about the Tamron and Cosina manufacturing correlation and lens factories in ...

Who manufactured the Vivitar Series 1 19-35mm F3.5-4.5 lens ? I initially thought it was made by Cosina . which looks identical to it.  The lens is also rebranded as Quantaray. However, now I see this:

I do it the exact same way you do.

I believe there were two versions of the FL 50mm F1.8.  Early version were said to be older R mount optics in a new body.  I believe they also used Thorium Dioxide ingredients.  Later FL 50mm F1.8 ...