[R. Wethereyet]

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Recently, I sold my Sigma 70-300mm telephoto lens as part of a "kit" deal to a newer photographer. I had picked it up used a few years ago for $100 CAD ($75 USD). It was "good enough" although it had an issue with Chromatic Aberrations, soft focus issues at many focal lengths ... it got the job done. I still have my Tamron 70-200mm f/2.8 that I love and I thought I could be happy just using that lens and cropping where needed.

As time goes on, I find myself yearning for a longer reach lens. I have done some research and thought either the Sigma 120-400mm or the Sigma 170-500mm would be good alternatives. It seems that the 170-500mm is a very rare bird - cannot find one for sale anywhere for any price. The 120-400mm can be found if you search hard enough - currently 2 for sale in the marketplace ($900 & $400), but as I look through photos taken with the 120-400mm lens, I am not impressed by the image quality. Even though they both have a 9.0 rating on the lens reviews ... I don't see that quality coming through in the images on-line.


I am looking for something of reasonable quality (better than the 70-300), for somewhere in the $300-$750 USD (used) range. So far I cannot come up with anything of reasonable quality. Pentax does have the 55-300mm as an option but I am hoping for something in the 400-500mm range.

Any suggestions or personal experiences with the 120-400 or 170-500?

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Last edited by R. Wethereyet; 11-13-2018 at 03:21 PM.

[pepperberry farm]

why not an F* or FA* or even a DA* 300mm prime?

[R. Wethereyet]

why not an F* or FA* or even a DA* 300mm prime?

Thanks Pepperberry farm. Yes, the 300mm f/4.0 is definitely an option (rating of 9.67). It is a bit above my budget but it hits the quality that I am looking for, so the investment would be worth it (once I convince a certain party in my household). The cropping from 300mm images would be less than the 200mm obviously.
SMC Pentax-DA* 300mm F4 ED [IF] SDM Reviews - DA Prime Lenses - Pentax Lens Reviews & Lens Database




Also, the 55-300mm (rating of 8.53) is an option if I give up the 400mm+ idea. The price is right and the WR rating is attractive too.
HD Pentax-DA 55-300mm F4-5.8 ED WR Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database


The 150-450mm beast would be great but the cost ($2000) and the weight (2000g) are big detractors from buying this lens
HD Pentax-D FA 150-450mm F4.5-5.6 ED DC AW Reviews - D FA Zoom Lenses - Pentax Lens Reviews & Lens Database

[SSGGeezer]

I have my 120-400 for sale and it is a fine lens, but best at 360mm and below. If my skills aren't up to snuff, I wouldn't blame it on the lens, but on the fact I always shoot it hand held. Is your 900 price due to customs fees or something? I could ship to Canada for only a few dollars more than here in the US. I know that Pepperberryfarm has gotten better results with the lens I sold him!

[DeadJohn]

... I still have my Tamron 70-200 f/2.8 ... Pentax does have the 55-300mm as an option but I am hoping for something in the 400-500mm range ...

I assume you want autofocus.


A 2x teleconverter would turn your 70-200 into 140-400 f/5.6. I don't know much about TC options but I think some 3rd party 2x support the screwdrive AF on your 70-200. Miscellaneous Lenses for Pentax: Teleconverters (All Brands) - Pentax Lens Review Database


I have a Pentax 55-300. Any variant of the 55-300 (DA-L, DA, HD, PLM) has good optical quality for the price. You can do some cropping with it but not too much.

My Sigma 50-500 is good but probably outside your budget. Image-wise it's better than 55-300, not as good as 150-450. Prices on 50-500 nearly doubled after being discontinued. Main limitation with this lens is f6.3 requires higher ISO.


A used DA* 300 f/4 might fit in your budget. That lens is sharp enough to crop quite a bit. You can optionally add the Pentax 1.4x teleconverter when budget allows, if you want more reach instead of cropping.

Final consideration, Tamron Adaptall 300/2.8 plus Pentax 1.7x AF. I was shopping for this lens for a while and expect delivery today 300/2.8 manual focus for astrophotography. 510/4.8 autofocus for wildlife; I plan to compare it against my Sigma 50-500.

[SSGGeezer]

I would also like to point out that any images uploaded here are not going to be over 1 Megapixel in size so you are not getting the real image as shot on higher resolution cameras.
Here is one at 400mm from my 500px page.Greedy Guy by Thomas Needham - Photo 260817293 / 500px
or here
Plum Yummy by Thomas Needham - Photo 258311487 / 500px


Love your name here as my father in law taught the kids to ask that on all road trips, no matter how far we were going. And as they say in Maine, "you can't get there from heah!"

[aslyfox]

well if the OP wants a big long lens:

SMC Pentax 135-600mm F6.7 K

https://www.pentaxforums.com/lensreviews/SMC-Pentax-K-135-600mm-F6.3-Zoom-Lens.html

Long lens for sale:SMC Pentax 135-600mm F6.7 K - PentaxForums.com

is for sale in the market place

I know nothing about it or the seller

and no AF

[R. Wethereyet]

I assume you want autofocus.


A 2x teleconverter would turn your 70-200 into 140-400 f/5.6. I don't know much about TC options but I think some 3rd party 2x support the screwdrive AF on your 70-200. Miscellaneous Lenses for Pentax: Teleconverters (All Brands) - Pentax Lens Review Database


I have a Pentax 55-300. Any variant of the 55-300 (DA-L, DA, HD, PLM) has good optical quality for the price. You can do some cropping with it but not too much.

My Sigma 50-500 is good but probably outside your budget. Image-wise it's better than 55-300, not as good as 150-450. Prices on 50-500 nearly doubled after being discontinued. Main limitation with this lens is f6.3 requires higher ISO.


A used DA* 300 f/4 might fit in your budget. That lens is sharp enough to crop quite a bit. You can optionally add the Pentax 1.4x teleconverter when budget allows, if you want more reach instead of cropping.

Final consideration, Tamron Adaptall 300/2.8 plus Pentax 1.7x AF. I was shopping for this lens for a while and expect delivery today 300/2.8 manual focus for astrophotography. 510/4.8 autofocus for wildlife; I plan to compare it against my Sigma 50-500.

Autofocus ... Yes...my as astigmatism plays tricks with manual focus (Thank goodness for the little green light in the viewfinder) ;-)
I have a manual Soligor 2x teleconverter that I have used a bit. I find the image quality is diminished drastically when I use it. I should probably look for a newer 1.4 version that is more compatible with my K-3 body & autofocus lenses. Thanks for the link - I will give it a read.

Congrats on the Tamron Adaptall - let us know how it works out for you.

[normhead]

For a budget lens , the 55-300 PLM is the one. For longer, the DA*300 with the 1.4 TC is the preferred option but well out of your budget range. I don't find the old FA and FA* glass to be very good options. The price never reflects the amount of use the original owner put on it and the number of years old it is. I believe there might be still an F 1.7x AF Adapter (1.7x TC, limited AF for manual lenses) for around $300. It's just hard to find something to put it on.

That and something like this might work for you, but I can't vouch for it.
Exc+ SMC Pentax 300mm f 4 f/4 PK Lens *7312245 | eBay

Looking at the lens review numbers, probably not. That's a 50/50 type score.
https://www.pentaxforums.com/lensreviews/SMC-Pentax-K-300mm-F4-Lens.html

Anyway, that's what I'd do, look on eBay (or the forum marketplace) , look up the lens in the lens review section. You might find a combo you like. Subtract 5 from the forum rating numbers and they'll give you an accurate rating out of 5. So tis is 7.77 with heavy aberrations. That would be 2.77/5. P:us the aberrations will be heavily magnified by the TC so that setting is important for any lens you think you might use with a TC.

Hopefully that's enough to get you started. Personally, for lenses to be used with TCs, I like lenses rated 9 or higher.

[R. Wethereyet]

I would also like to point out that any images uploaded here are not going to be over 1 Megapixel in size so you are not getting the real image as shot on higher resolution cameras.
Here is one at 400mm from my 500px page.Greedy Guy by Thomas Needham - Photo 260817293 / 500px
or here
Plum Yummy by Thomas Needham - Photo 258311487 / 500px


Love your name here as my father in law taught the kids to ask that on all road trips, no matter how far we were going. And as they say in Maine, "you can't get there from heah!"

Thanks SSGGeezer, those are the sharpest shots that I have seen with that lens. I did a search on Flickr and was not impressed. These restore my confidence. It could also be that the lenses on Flickr needed some micro-focus adjustments.

Thanks re "R. Wethereyet" name. On our family road trips, I would ask my father where we were going ... his reply was either, "We are just going to follow our noses and see what we find", or "we are going to see a man about a dog" ( we only got a dog once in 15 years of road trips ...)

---------- Post added 11-08-2018 at 11:45 AM ----------

For a budget lens , the 55-300 PLM is the one. For longer, the DA*300 with the 1.4 TC is the preferred option but well out of your budget range. I don't find the old FA and FA* glass to be very good options. The price never reflects the amount of use the original owner put on it and the number of years old it is. I believe there might be still an F 1.7x AF Adapter (1.7x TC, limited AF for manual lenses) for around $300. It's just hard to find something to put it on.

That and something like this might work for you, but I can't vouch for it.
Exc+ SMC Pentax 300mm f 4 f/4 PK Lens *7312245 | eBay

Thanks Normhead for the helpful comments. I will take a look at the ebay lens.
I think I am narrowing the choices down to the 120-400mm or a DA* 300mm + TC of some sort.

---------- Post added 11-08-2018 at 11:49 AM ----------

I have my 120-400 for sale and it is a fine lens, but best at 360mm and below. If my skills aren't up to snuff, I wouldn't blame it on the lens, but on the fact I always shoot it hand held. Is your 900 price due to customs fees or something? I could ship to Canada for only a few dollars more than here in the US. I know that Pepperberryfarm has gotten better results with the lens I sold him!

The other 120-400mm in the marketplace is listed at $750USD so my $900 would be $CAD

---------- Post added 11-08-2018 at 11:56 AM ----------

For a budget lens , the 55-300 PLM is the one. For longer, the DA*300 with the 1.4 TC is the preferred option but well out of your budget range. I don't find the old FA and FA* glass to be very good options. The price never reflects the amount of use the original owner put on it and the number of years old it is. I believe there might be still an F 1.7x AF Adapter (1.7x TC, limited AF for manual lenses) for around $300. It's just hard to find something to put it on.

That and something like this might work for you, but I can't vouch for it.
Exc+ SMC Pentax 300mm f 4 f/4 PK Lens *7312245 | eBay

Looking at the lens review numbers, probably not. That's a 50/50 type score.
SMC Pentax 300mm F4 Reviews - K Prime Lenses - Pentax Lens Reviews & Lens Database

Anyway, that's what I'd do, look on eBay (or the forum marketplace) , look up the lens in the lens review section. You might find a combo you like. Subtract 5 from the forum rating numbers and they'll give you an accurate rating out of 5. So tis is 7.77 with heavy aberrations. That would be 2.77/5. P:us the aberrations will be heavily magnified by the TC so that setting is important for any lens you think you might use with a TC.

Hopefully that's enough to get you started. Personally, for lenses to be used with TCs, I like lenses rated 9 or higher.

Agreed Norm, great tip on the ratings! I am looking for lenses rated at 8.5 or higher. I guess I am searching for "sleeper" lenses that are sharp and won't break the bank.

[normhead]

Thanks SSGGeezer, those are the sharpest shots that I have seen with that lens. I did a search on Flickr and was not impressed. These restore my confidence. It could also be that the lenses on Flickr needed some micro-focus adjustments.

Thanks re "R. Wethereyet" name. On our family road trips, I would ask my father where we were going ... his reply was either, "We are just going to follow our noses and see what we find", or "we are going to see a man about a dog" ( we only got a dog once in 15 years of road trips ...)

---------- Post added 11-08-2018 at 11:45 AM ----------



Thanks Normhead for the helpful comments. I will take a look at the ebay lens.
I think I am narrowing the choices down to the 120-400mm or a DA* 300mm + TC of some sort.

---------- Post added 11-08-2018 at 11:49 AM ----------




The other 120-400mm in the marketplace is listed at $750USD so my $900 would be $CAD

---------- Post added 11-08-2018 at 11:56 AM ----------




Agreed Norm, great tip on the ratings! I am looking for lenses rated at 8.5 or higher. I guess I am searching for "sleeper" lenses that are sharp and won't break the bank.

In my experience, sooner or later you capitulate and break the bank. But enough about me.

[R. Wethereyet]

In my experience, sooner or later you capitulate and break the bank. But enough about me.

So true :-D ... with winter coming on, I am trying to stay out of the doghouse!!

[SSGGeezer]

So true :-D ... with winter coming on, I am trying to stay out of the doghouse!!

Alberta is even colder than Maine and Ontario! So stay inside!

[Buffy]

It has been said that you can describe lenses with three words--long, sharp, inexpensive--but you can only pick two of the three at a time.

Over time I have had both versions of the Sigma 170-500 and found both a bit soft at the long end and, being slow, autofocus was difficult in anything less than afternoon sun. Lens creep was also a nuisance with both.

[clackers]

Over time I have had both versions of the Sigma 170-500 and found both a bit soft at the long end and, being slow, autofocus was difficult in anything less than afternoon sun. Lens creep was also a nuisance with both.

Yeah, I've got the 150-500. For all their size, they and the more modern Tamron and Sigma zooms up to 600mm are still consumer standard, very slow at the long end and not sharp. The small aperture means that add a TC and there's trouble focusing.

300mm f4 seems to be a sweet spot in performance, price and weight across brands. Add a TC if needed, you're still above f8 for the AF module to cope with.