How to mount older Pentex/Vivitar/Tamron lenses to T1i

Sorry Roy..your English isn't so great. Could you try and re-phrase the question please?

There are adapters that will allow you to mount those lenses to your camera body as long as they meet a few conditions. The Pentax should fit as long as it is a M42 mount and not a M39 mount (for rangefinders). The Tamron and the Vivitar might work, but you'll need to know what bodies they were originally ment for in order to get an adapter or to find out if their register length is appropriate for adapting to the EOS bodies. So, first things first, after you find out what those were ment for, go find a list of lens register sizes online. Type "register" in the search box on this site and you might even encounter a list here, but I am not certain if that would be the case. There are many adapted lens tutorials online for manual lenses.

This kind of stuff is easy to figure out.

I searched Google for "Pentax-A 1:1.7 50 mm" and came up with this link: http://www.pentaxforum​s.com …tax-A-50mm-F1.7-Lens.html that says that your lens has a 49mm filter diameter.

Then, I searched Amazon for "49mm Macro Reverse" and came up with this link.

There's your reversing ring for only $8.95.

Now that I've showed you how to find this, you should be able to find reversing rings for your other lenses. You'll have a lot more friends on this forum if you do as much searching as possible before asking your question (and expecting someone else to do your work for you). Google is wonderful, type in almost any question and you'll find several answers. Personally, I spent a couple hours on this forum reading about macro photography before asking any questions. Almost every question you can imagine has already been answered - you just have to know how to use the search function.

Good luck to you. The first step in using a modern DSLR is to learn how to do research on the internet. Come back to this forum when, even after reading everything available, you are still genuinely stumped and everyone will be happy to help you.