[DeadJohn]

I'm considering a new long lens primarily for aviation photos. I currently use a DA 55-300 and am generally very satisfied with it but more reach would mean less cropping.

I was headed towards the Sigma 50-500 but the review at Sigma 50-500mm F4.5-6.3 APO OS HSM - Review - PentaxForums.com has me concerned. The comparison shots of the cactus cropped at 240mm looks better than 500mm. It appears that the 50-500 is "tuned" for it's best IQ at the short end while the Pentax 55-300 seems tuned for the long end. The 50-500 might not be any better than crops from my current 55-300. Did the reviewer got an exceptionally bad lens due to poor QC or is the 50-500 frequently that soft?

The Sigma 150-500 is less expensive but I haven't seen anything that says it's sharper than the 50-500.

Anyone suggest other lenses that would be a significant improvement over my DA 55-300 for airshows? My budget expectations were set based on the 50-500 so I want to keep it under $2000.

The DA * 300 is a tempting alternative. It's a good blend of IQ, max. aperture, and compactness. WR is a plus. It's fast enough to handle a teleconverter if I ever want more reach instead of cropping. The inability to zoom out would limit it's use when I'm near the runway (but I have the 55-300 for that). I'm also wary of Pentax' short 1-year warranty.

Or maybe the Tamron or Sigma 70-200 2.8 plus 2x teleconverter?

[LaurenOE]

Good questions. I'd like to hear what people say.

[pearsaab]

that is one heck of a question with multiple answers...i have the 70-200 sigma 2.8, the 60-250 pentax 4, the 300 pentax 4, the 50-500 sigma 4.5-6.3 and pentax 1.7x adapter, tamron 1.4x and sigma teleconverters so i can cover just about any scenario....the 50-500 is an excellent lens and i generally shoot it at 500mm and am extremely happy with the quality...i'm at work so i don't have any examples to show...i have even considered buying the 500 but i do like the range the 50-500 offers...i am assuming you handhold when you take the pictures since the action can be everywhere...my 2 cents is the 50-500 gets exhausting to handhold but can be done especially if you park yourself somewhere and can lean the lens on something... i have also used it with a monopod with a gimble mount and that works but sometimes i just don't want the weight to deal with...if i want to get in the 500 range without carrying the bigma, i will use the pentax 300 with the 1.7x adapter and pictures are excellent and once you get the hang of how to use the adapter you can focus reasonably comparable to the normal focus time...obviously you can't shoot below 6.8 but i would think if you are taking air pictures you would be using a higher apeture with a high shutter speed...the tamron 1.4x will work with the 60-250 but not the 300 and focus is slower...i can't say i am very impressed with the 2x sigma, the 1.4 is ok and have used it with the 70-200 sigma but that isn't going to gain you the distance you want...so my 2 cents is go out and rent a 50-500 and i think you will be pleased but the weight and the extending lens does takes some getting used to...the other option which will be alot more expensive is the pentax 300 (which is weather resistent) with the 1.7x adapter but the adapter is not WR so kind of defeats the purpose of a WR lens

[L33tGreg]

Used Sigma 100-300/4 with 1.4x TC. Effective 140mm-420mm f/5.6 with great IQ.

[Lowell Goudge]

I have the original sigma APO 70-200/2.8 EX Non DG Non Macro and it works very well with a TC but newer lenses especially once they introduced macro focusing got softer at the long end and soft wide open as well. the latest HSM II version gets great reviews , so the issue is now after 3 optical formulas, corrected, but the HSM has no corresponding teleconverter to go with it.

I also use a K300/4 with the SMC-F 1.7x TC and this works well, but no zoom, and not the sharpest at infinity, works much better in the 100 foot and closer range. The 1.7x works very well I hear with the DA300.

I also have an old MF 200-500/5.6 zoom, but at 6+ pounds it is tripod bound, not the greatest for an air show.

[Adam]

For air shows you subjects won't be as far away, so I think the 50-500mm will work fine there.

[LaurenOE]

It's still confusing. So is the currently stocked bigma at B&H, sharp at 500mm and represent the best lens available for Pentax mount in this range?

[pearsaab]

here is a cattail using the 50-500...the original picture is at 500mm F7.1 1/50 iso160...the second is cropped by factor of 4....

[LaurenOE]

here is a cattail using the 50-500...the original picture is at 500mm F7.1 1/50 iso160...the second is cropped by factor of 4....

I think that is pretty sharp. Is that from a current Bigma?

[joe.penn]

@DeadJohn - one thing to note is if you are shooting these jets/planes/choppers/etc. while flying you will be shooting a lot of extremely high contrast shots, whichever lens you choose you may want to check out it's ca/pf performance as loss of sharpness (unrecoverable) is a major issue byproduct of ca/pf...

[johnha]

You don't mention what you're most interested in photographing. A zoom is probably essential if you're interested in a mix of fast jet & larger aircraft/formations, and if you want to shoot prop planes, shutter speeds higher than 1/250th risk showing stationary props (a big heavy lens might be a problem).

[DeadJohn]

here is a cattail using the 50-500...the original picture is at 500mm F7.1 1/50 iso160...the second is cropped by factor of 4....

I think that's plenty sharp especially considering how much cattails sway in the wind. How far away was the cattail? If I understand you correctly the 1st sample image is the entire original 16mp area simply resampled to 1024x768 but not cropped.

In that case the cattail seems pretty close to the camera and shows the lens is sharp when focused on nearby objects. It doesn't test sharpness on far objects which was the main IQ problem noted in the PF review. Airborne craft will be further away than the cattail and may be blurry if the review is accurate.

[DeadJohn]

You don't mention what you're most interested in photographing. A zoom is probably essential if you're interested in a mix of fast jet & larger aircraft/formations, and if you want to shoot prop planes, shutter speeds higher than 1/250th risk showing stationary props (a big heavy lens might be a problem).

I'm dealing with a mix of jets & props, solo & formation. I expect to see the Blue Angels, F22, B-17, P-51, etc. near the end of the month. I understand what you're saying about props ... some prop blur is desirable. My panning technique is okay (and I think the Bigma's stabilization mode 2 is designed for panning, another plus for that lens) so 1/250 handheld at 500mm seems manageable.

[pearsaab]

yes it is...i bought it about 1 year ago...the first picture is the full 16mp picture resampled...i don't know what the distance was but the lens was fully extended...what are you looking for specifically and maybe i can try some shots this weekend

[rawr]

Lenstip.com have a useful and positive review of the newer OS version 50-500 Bigma. The resolution results show that the lens can indeed deliver useful results.

If airshows aren't your everday gig though perhaps you could just hire something more capable like the Sigma 200-500 f2.8 for a few days as required