[MossyRocks]

4. Astro (this is a stretch goal. Am happy shooting wide angle lenses wide open for this)

I assume that the Tak 135/2.5 is the bayonet takumar, and not the M42 mount one. I have the Bayonet Takumar 135/2.5 and got it recently to see how it does with astro. I've only used it once and haven't' done a extensive test with it but at first sniff it is pretty good for astro and for someone who would be just starting out it wouldn't be the limiting factor. As far as the old 200/3.5 takumar it is an excellent lens for astro and if I didn't already have a lens at the spot that is almost as good I would want it. I wrote up a detailed review of the Takumar 200/3.5 for astro here.

In looking at your other lenses the only other one I would consider for astro would be the M 50/1.4. The 50/1.4 (S-M-C or newer) is a good lens for wide field astro and you can get a lot of stars in the frame with it. You can fit all of Orion in the frame and most of the other constellations will fit in the frame too. While it isn't very good at f/1.4 as it will bloat starts, but run it at 2.8 and you will get some great results. I wouldn't bother with your zooms for astro.

On the wide/ultra wide end of things for astro you are lacking. Unfortunatly things will get expensive if you want reasonably good results with something wider than 35mm, but a 35mm lens would be a good cheap option. I have the DA AL 35/2.4 and it give acceptable results wide open at 2.4 and does really well at f/4. Your Pentax 28mm lenses won't do very well for astro, expect disappointment. Unfortunatly the really wide lenses didn't good for astro until recently and are expensive even used. Samyang/Rokinon has some cheaper options that if you get a good copy of produce good results for astro but even they aren't super cheap. I use the Laowa 12mm f/2.8 Zero-D lens and it is very good for astro but it isn't cheap by any measure.

[boriscleto]

Five 50mm lenses? Congratulations, you have LBA. There is no cure.

[zeebanker]

So this is what I'm hearing:

28mm:
1. Albinor w/macro F2.8
2. Pentax M F3.5
3. Super Tak F3.5

50mm:
1. Pentax M F1.4
2. Pentax M F1.7
3. Pentax M F2.0
4. Pentax A F2.0
5. Pentax DA F1.8

55mm:
Super Tak F2.0

135mm:
Tak F2.5

200mm:
Tak F3.5

18-55mm:
Pentax DA F3.5-5.6

60-300mm:
Sears F4.0-5.6

70-200mm:
Tak A 4.0

70-300:
Sigma DG Macro F1.4-5.6

I left the Sigma on because its an ok, auto focus lens. So that leaves me with 5 and I should complement them with something wide angle.

Look for some upcoming glass on the buy/sell forum soon (unless you PM me and make me an offer). These are all functional lenses in "fair" to "good" condition. No optical defects, but the older ones have cosmetic blemishes consistent with their age.

Thanks everyone!

[zeebanker]

BTW, I realized that I left out the "SMC" notation on all my Pentax and Taks. I assumed that they were default, but am learning that it may not be so. Nearly all my lenses are SMC.

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Last edited by zeebanker; 09-09-2020 at 01:12 PM.

[zeebanker]

Five 50mm lenses? Congratulations, you have LBA. There is no cure.

That's exactly why I'm trying an early surgery before things get past a "no going back" stage.

[Topsy]

That's exactly why I'm trying an early surgery before things get past a "no going back" stage.

Good luck! :P

If you were a little closer to me I'd have the 135/2.5 off you.
I luckily never tried to get rid of any

[Just1MoreDave]

I think with a low budget, some time and a pile of existing lenses, the best path is to test and use them until you know for sure that you like it or hate it. For example, it should be easy to see why an M50 f1.4 is nicer than an M50 f2. Test the 70-200 against the 60-300 and the 70-300. I do this kind of comparison often. Sometimes I can see very clearly where a lens is bad. Sometimes I discover the lenses are close enough in performance so I can pick based on other factors. Maybe the A50/2 is just fine and you like the convenience of the aperture and small size.

Then don't look to complete a collection, look to upgrade one area at a time. That way you don't have to buy six compromise lenses, just one good one. The goal should be if you want to take a portrait, you know exactly what lens does that.

If you can't resist buying something right now, set a dollar amount not to exceed for the HD 55-300. As mentioned above, you can't get the PLM version because it won't work on your camera. That's OK because you can choose from the large supply of used lenses as others upgrade to the PLM. I set a price of $100 which I thought was way too low. It wasn't.

[mikesbike]

So this is what I'm hearing:

28mm:
1. Albinor w/macro F2.8
2. Pentax M F3.5
3. Super Tak F3.5

50mm:
1. Pentax M F1.4
2. Pentax M F1.7
3. Pentax M F2.0
4. Pentax A F2.0
5. Pentax DA F1.8

55mm:
Super Tak F2.0

135mm:
Tak F2.5

200mm:
Tak F3.5

18-55mm:
Pentax DA F3.5-5.6

60-300mm:
Sears F4.0-5.6

70-200mm:
Tak A 4.0

70-300:
Sigma DG Macro F1.4-5.6

I left the Sigma on because its an ok, auto focus lens. So that leaves me with 5 and I should complement them with something wide angle.

Look for some upcoming glass on the buy/sell forum soon (unless you PM me and make me an offer). These are all functional lenses in "fair" to "good" condition. No optical defects, but the older ones have cosmetic blemishes consistent with their age.

Thanks everyone!

I think you are on the right track here, getting rid of redundancy. Maybe reconsider keeping the 135mm f/2.5 TAK- I don't know this lens, but it has a fast aperture for the FL. Instead, also get rid of the Sigma 70-300mm. it is definitely NOT f/1.4-5.6 but more like f/4-5.6 and is just fair especially at the long end. Then get just two lenses- the older, non PLM Pentax HD 55-300mm f/4-5.8 WR a very good lens and B&H has a good deal going on it right now (I've had this lens for years), and the DA 18-135mm f/3.5-5.6, a great all-around lens with excellent AF and has the wide angle you need at the same time (I've had this lens also for years, and I shoot with the K-5 IIs as well as the KP).

[Wasp]

For landscapes you to go wide. I have a Sigma 10-20mm f/3.5 that I am very happy with. Sigma has discontinued their K mount line, but there are used ones around. You might even find a new old stock copy. There are various options in ultrawide primes that are available new, but I can't comment from experience.

For planes, that 300mm is not always long enough. A Sigma 150-500mm would work well. I have an SMC Pentax A 400mm f/5.6 myself. The manual focus is not really a problem with planes, since they are usually quite far away.