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Thanks Dan. This looks like another great resource. If you haven't seen it, there's a similar collection of lens designs from patents, etc. at http://www.lens-designs.com/. All of the designs are...

Hugo, thanks for the suggestion. 36 bids, from $299 up to $2,550... that lens is hot! Looks like a challenge to me, but I don't know if COTS lenses will allow me to get anywhere. I'll have to take a...

Thanks Dan. This looks like a great resource that you've assembled and maintained!

Hi Fred.

Unfortunately, switching materials is not so simple. Each optical glass (or plastic) has a refractive index and dispersion that's taken into account in the Cooke triplet design so that...

Good question! I doubt these stock lens systems will ever be better than what you could achieve with custom optics, but they can be pretty good if you really want to DIY. Perhaps the better question...

I agree - I tried a few designs with the Thorlabs' meniscus lenses and unfortunately wasn't able to get anywhere.

Here's an updated optical design that achieves similar performance at f/6.7. I...

That's right. This lens system was designed for imaging on a 4x5 format and I didn't consider a larger field of view. While light will get through the system at a wider angle, the performance drops...

Good to know, thanks. I might play around a little with a stronger negative element to increase the focal length and reduce the vignetting then before moving over to the mechanical design.

To make this sort of lens work well, the surface curvatures, glass choice, and spacing are all critical. I haven't seen this sort of detail published for Nikon or Canon lenses, which means that...

Thanks! I did a quick check and increasing the air gap between the two front lenses to 1 mm results in no appreciable difference in performance. In this case, the reoptimized air gaps are:
...

Hi Everyone,

I was inspired by Nodda Duma's popular thread A DIY 177mm f/8 Cooke triplet for 4x5 from off-the shelf lenses that YOU can build and thought I'd take a crack at improving the...