Vintage lens

[powerlord]

maybe worth using a Bahtinov ? bit of card and a knife is all you need to make one right for the lens:

https://skeye.rocks/tools/mask/

usually printing and cutting one out is an option, but with a 135 it'd be pretty fiddly I reckon.

Prob needs 3d printing. do you have access to a 3d printer ?

You did well to get a takumur135 for 15 quid. I got one a few years ago which had sticky blades cheap.. took it apart to clean the blades, and it's never properly worked since - nearly went mad putting it back together..but still not right.

stu

[Ratlet]

5 minutes ago, powerlord said:

maybe worth using a Bahtinov ? bit of card and a knife is all you need to make one right for the lens:

https://skeye.rocks/tools/mask/

usually printing and cutting one out is an option, but with a 135 it'd be pretty fiddly I reckon.

Prob needs 3d printing. do you have access to a 3d printer ?

You did well to get a takumur135 for 15 quid. I got one a few years ago which had sticky blades cheap.. took it apart to clean the blades, and it's never properly worked since - nearly went mad putting it back together..but still not right.

stu

I might give that a try.  The trick as @alacant mentioned is that in focus the Takumars only focus blue and green so you need to get in focus and then back out slightly.  Usually they are well behaved and can produce decent results, although in this case I missed the mark on both images (although I'm still quite happy with them as they captured some nice parts of the sky).

I'm going to go for some CA free shenanigans next though and use the 130PDS without a coma corrector.  The 533C is small enough a sensor that the coma is pretty well controlled without a corrector.  Just need to decide what to image.  Got a bahtinov mask for that thankfully.

[alacant]

46 minutes ago, Ratlet said:

you need to get in focus and then back out slightly

Exactly. The mask will get you only as far as the red halo. 

49 minutes ago, Ratlet said:

130PDS without a coma corrector

It doesn't get much more apochromatic than that. Excellent idea.