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Sigma 300mm F2.8 EX APO DG

Reviews Views Date of last review
8 45,252 Mon July 21, 2014
Recommended By Average Price Average User Rating
100% of reviewers $2,436.86 8.75
Sigma 300mm F2.8 EX APO DG

Sigma 300mm F2.8 EX APO DG
Sigma 300mm F2.8 EX APO DG
Sigma 300mm F2.8 EX APO DG
Sigma 300mm F2.8 EX APO DG


The Sigma 300mm F2.8 EX APO DG lens is compact fir its focal length and aperture.It incorporates two Extraordinary Low Dispersion glass elements to reduce chromatic aberration. Itfeatures internal focusingfor responsive and fast autofocus speed. A detachable tripod socket and rotatable drop in filter holder are included.

With the use of the optional Sigma APO teleconverters, this lens can be used as a 420mm F4 AF ultra-telephoto lens with a 1.4X EX teleconverter, or a 600mm F5.6 AF ultra-telephoto lens with a 2X teleconverter.

Thedrop-in 46mm filter holder in the rear part of the lens barrel can be rotated to facilitate the use of a polarizing filter.

The tripod collar is removable.

Sigma 300mm F2.8 EX APO DG
©, sharable with attribution
Image Format
Full-frame / 35mm film
Lens Mount
Pentax K
Aperture Ring
Yes (A setting)
Automatic, 9 blades (rounded)
11 elements, 9 groups
Mount Variant
Check camera compatibility
Max. Aperture
Min. Aperture
AF (screwdrive)
Min. Focus
250 cm
Max. Magnification
Filter Size
46 mm (Rear drop-in)
Internal Focus
Field of View (Diag. / Horiz.)

APS-C: 5.5 ° / 4.6 °
Full frame: 8.3 ° / 6.9 °
Lens Cap
Weather Sealing
Other Features
Drop-in Filter Holder,Push-pull AF/MF Focusing Ring,Tripod Mount
Diam x Length
119x213 mm (4.7x8.4 in.)
2390 g (84.3 oz.)
Production Years
(in production)
$3399 USD current price
User reviews

Buy Lens: Buy the Sigma 300mm F2.8 EX APO DG
Price: $3399
Mount Type: Pentax KAF3 (in-lens AF only)
Price History:

Add Review of Sigma 300mm F2.8 EX APO DG Buy the Sigma 300mm F2.8 EX APO DG
Sort Reviews by: Date | Author | Rating | Recommendation | Likes (Descending) Showing Reviews 1-8 of 8

Registered: July, 2013
Location: At a Starbucks, most likely!
Posts: 123

1 user found this helpful
Lens Review Date: July 21, 2014 I can recommend this lens: Yes | Price: None indicated | Rating: 9 

Pros: Sharp like a scapel
Cons: AF hunts, often incosistent
Sharpness: 10    Aberrations: 8    Bokeh: 10    Autofocus: 8    Handling: 8    Value: 9    New or Used: Used    Camera Used: Pentax K-5iis   

This lens is a solid 9.5 for me. I chose the Sigma EX 300mm f2.8 since AF works well with both the dedicated 1.4x and 2.0 teleconverters. (I've read that people even stack both the TC with satisfactory results but i have to confirm that first hand). The previous owner of this lens, also a contributor here at the forum "garyk" was gracious enough to sell me his excellent used, re-chipped and calibrated copy and as he also stated in his March 15, 2010 review this lens it sharp from f2.8. (Mind you the DOF is razor-thin, so there's isn't a lot of use shooting wide open but when stopped from f3.2 - onward is an excellent performer.) The Bokeh on this lens is simply stunning, in my view almost as good as my Pentax-F 135mm f2.8.
These are the pictures i took the first day it arrived, the photos are in shooting order, the first picture being the bird on the rock.

K-5iis + Sigma 300mm f2.8 shot at f3.2

K-5iis + Sigma 300mm f2.8 + Sigma 1.4x TC shot at f4
New Member

Registered: November, 2006
Location: Brooklyn, NY
Posts: 16

1 user found this helpful
Lens Review Date: July 1, 2013 I can recommend this lens: Yes | Price: $3,395.00 | Rating: 9 

Pros: fast, sharp, works well w/ Sigma 1.4x converter
Cons: heavy
Sharpness: 10    Aberrations: 8    Bokeh: 9    Autofocus: 8    Handling: 9    Value: 8    New or Used: New   

I generally cannot disagree w/ the run of previous reviews of this lens.

How well (or poorly) it works w/ the Sigma converters is largely a matter of users' expectations. IMO the IQ w/ the 1.4x is still close to excellent; significantly better than cropping the image done w/o the converter, and with the benefit of better magnification in close-ups. With the 2x there is a greater loss of IQ, but combo is still usable and still yields better IQ than cropping the 300mm image; the biggest loss IMO is in contrast. Of course a 600mm combination is very vulnerable to subject motion, so high shutter speeds are called for in many situations, but that would be the same issue with almost any very long lens or combination.

My personal (admittedly somewhat picky) complaint is that Sigma supplies this w/ TS-21 tripod collar, which works as a tripod socket, but actually gets in the way when hand-holding. (Clearance between the barrel and handle is too narrow to allow use as a grip.) This means spending an additional $150 for the optional TS-41 which works as well as a socket and as a grip for hand-holding, unless one removes and replaces the TS-21 whenever switching from hand-holding to tripod mounted.

Registered: February, 2010
Location: Blunsdon,Wiltshire, UK
Posts: 1,136

2 users found this helpful
Lens Review Date: January 17, 2012 I can recommend this lens: Yes | Price: $2,147.18 | Rating: 10 

Pros: Very sharp,lightweight,
Cons: None
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 10    Handling: 10    Value: 10    New or Used: Used   

I purchased this lens secondhand less than a year old.
I am totally happy with the results it produces.
Goldfinch juvenile being fed by Gary Chalker, on Flickr

Swallow feeding juvenile by Gary Chalker, on Flickr

Swallow feeding juvenile by Gary Chalker, on Flickr

Swallow feeding juvenile by Gary Chalker, on Flickr

Swallow feeding juvenile by Gary Chalker, on Flickr

Swallow feeding juvenile by Gary Chalker, on Flickr

Swallow juvenile by Gary Chalker, on Flickr
Veteran Member

Registered: July, 2007
Location: Hong Kong
Posts: 431
Lens Review Date: October 21, 2010 I can recommend this lens: Yes | Price: None indicated | Rating: 8 

Pros: Build quality, good image and sharp.
Cons: Does suffer from CAs & purple fringing at and near wide open and at very high contrast edges.

I agreed to the comments of m8o, his review is a very good one. Focus is fast but sometimes just wouldn't autofocus with the subject right in-front of you. Furthermore, do not expect you can get good image quality with a 2x tele-converter with this lens, thus becoming a 600mm lens. I have tried the orginal Sigma 2x or Kenko AF 7 elements 2x, the image quality just not up to my expectation. I have tried the Pentax FA*300mm f2.8 with a 2x, the IQ is far much much more better. But of course, to be fair, this Sigma is much more cheaper than the Pentax. If using the Sigma as a 300mm f2.8 lens without any tele converter, then it is great and really worth for its price.

My sample images:

By adding the original Sigma 2x, the IQ is a little bit soft.
Inactive Account

Registered: February, 2010
Posts: 488

2 users found this helpful
Lens Review Date: March 15, 2010 I can recommend this lens: Yes | Price: $2,999.00 | Rating: 8 

Pros: Manually great optics, construction great.
Cons: Focus is so far out i cannot use auto focus

I purchased the lens because of the great reviews here. I am on assignment in S.E. asia. The lens arrived and packaged great, looks great. Optically it is very good. Manually focused it is better than i expected.
Problem: I have the k20d and even with the auto focus remaping, it is so far out of focus it is usless. When i focus manually it is superb. The problem is i shoot wildlife and is completly usless, and now since i am here It has to be sent back and fixed in the states. Very costly for me.
After i get it fixed i will sell it and all my pentax gear. The pentax is a good product but lens and such are not where it should be compared to Nikon and Cannon. These two top brands have outlets in almost every country and very easily fixed and serviced. It is a shame Pentax has let there market share drop to a point where it is just not practical to own there product. especially for someone who travel extensivly...
For me it is not a quality issue with pentax. It is a question if i can get lens and service while traveling. The answer to this is a resounding NO.
Sorry Pentax I am history now for good. I have held out untill this. Now i am jumping ship.

Back from Sigma service. Well it finally got fixed. Now i am a happy camper. The lens focuses very good. The quality is not bad either. So I am taking it from a bad rating to a fairly good rating. Only because you cannot get it serviced very fast if out of the country. Now i hear back in the states you can get very fast return times. I am now taking some very sharp pics.

Thought i would share this with you. I have had the sigma 300mm f2.8 in the service center 3 times now. finally with a new chip that the dealer here can reprogram it is really giving me shaaaarp images. If you buy this lens i highly recommend you get it calibrated with your camera and the new chip installed. A world of difference for me. I am so amazed at the images at 2.8, wide open It is just incredible. Now i cannot tell the difference in wide open and stopped down. And i am a crop every image heavily. Also i had to quit using the sigma 1.4 and 2.0 t.c.. It degrades the images fo much for me.

This is my last edit here. Since switching to the k-5 I can say. Without a dout the 300mm f2.8 lens is the winner in sharpness, between the 500mm f4.5 and the 300mm f2.8. The new K-5 really tells on a lens. And i can say the 300mm shines here. I visit the canon sites, and read the reviews on the Sigma 300mm f2.8 and they all just rave about it. I really thought i had a bad copy. Now with the k-5 I understand the reviews. The 500mm f4.5 at first seems sharper and really performes well at all stops. But, my copy of the 300 takes the prize. The 500 has a deeper FOV and seemes sharper because of this. As a daily shooter i am very convenced this is the case for my two copies..

All photo's here are with the 300mm f2.8 or the 500mm f4.5 Sigma lens. And the K-x camera body.

Registered: November, 2007
Location: Helsinki, Finland
Posts: 510
Lens Review Date: August 31, 2009 I can recommend this lens: Yes | Price: $2,300.00 | Rating: 8 

Pros: Balanced and compact for a 300/2,8. Build quality
Cons: No AF range limiter, no strap mounts (available as an extra)

This lens replaced my old faithfull MF Tamron 300/2,8 a year and a half ago.
Solid construction and pretty good optics, too. IQ and sharpnes pretty good wide open, and very good from f3,5 onwards. Pixel peepers may be able to find some minor purple fringing in areas of extreme contrast. But this is really insignificant, and can easily be corrected in post processing, should it be noticeable. AF works well thanks to the speed of the lens. Also with Sigmas 1,4 x and 2 x teleconverters. As usual, there is some loss of image quality, especially with the 2 x TC.
My copy has a little BF in both K10D and K7. However, this could easily be compensated with the AF adjustment in the body. Comes with a CP filter and Sigmas smart filter insertion system allowing the filter to be rotated inside the lens.

Registered: January, 2007
Location: Warsaw
Posts: 338
Lens Review Date: July 28, 2009 I can recommend this lens: Yes | Price: $1,500.00 | Rating: 9 

Pros: works with TC2 with AF
Sharpness: 10    Aberrations: 10    Bokeh: 10    Autofocus: 10    Handling: 8    Value: 9    New or Used: New   

After few sessions with this lens here there are some observations:
- great portrait lens in short-medium distance (up to 10 meters) - sharp from f2.8, great colours and bokeh
- heavy but handy - it is possible to take photos without any special support
- works with AF with Sigma TC1.4 and Sigma TC2 WITHOUT any problems
- works with Pentax AF1.7 and again without any problems supports its AF
- it is small enough to fit in my Lowepro backpack - mounted to my K20D

some sample shots are here
Veteran Member

Registered: July, 2007
Location: 40-55'-44" N / 73-24'-07" W [on LI]
Posts: 3,096
Lens Review Date: March 15, 2008 I can recommend this lens: Yes | Price: $2,280.00 | Rating: 9 

Pros: Stunning images produced sometime surprises me and has me saying "I took that?". The lens's capabilities outshines the meager skills of this 1/2 year D-SLR user. Fantastic sharpness, color and contrast.
Cons: Some CA/color fringing at and near wide open but only at very high contrast edges. No focus limiter is trying at times. Sometimes just wouldn't autofocus with the subject right in-front of you ( yes, subject further then minimum focus)

If there was a 9.5 I'd give it. But as it's either 9 or 10, I guess I have to go with a 9 [edit: I just changed it from a 10. I slept on it and decided the criticisms I'll offer won't allow for a 10. Not due to optical performance, but lack of a focus limiter that does make for frustration sometimes]. I am not going to give a gushy review, and sound like an advertisement for this stunner of a lens. It's fantastic, but let's be real. It is not w/o fault. But it does so much else good you almost forget about that. Getting it at the price of the 120-300mm f/2.8 zoom (not even made for Pentax mount) due to a listing error by 47th St. Photo doesn't hurt either ... expect to pay $2600 at present.

I wrote a few PM responses to a couple of people who asked for my thoughts about the Sigma 300mm f/2.8. Here's a re-work of them with some additions.

I used the lens extensively with the 1.4x and 2x Sigma TCs. I tried it with the 1.7x too but nothing 'serious' so I can't offer an opinion on that. You loose the in-lens focus replaced by the TC's focus when you do that, so I don't enjoy it as much ... at least not with this lens. As they say a picture is worth a 1000 words, so I guess I have 1,000,000 words or there abouts on the subject:
with over a 1000 pictures still to be converted! (I simply ran out of steam)

Not counting the travel pix and wide angle shots (which are not used w/the 300mm + TC are obvious), the wildlife pix are all taken with the 300mm f/2.8; with the pix on 070811 and 070812 as you noted taken with the 1.4x TC, and polarizing filter. The 1.4x is pretty invisible to the light coming through. Once we went to Ngorongoro Crater on 070814, I began using the 2x TC exclusively for the remainder of the trip. These are with a poorly cleaned/pitted UV filter; I put the wrong one in, having purchased a new one but using the 'bad' one the whole trip. without noticing :ugh:

The pix of my last day when I was leaving, at the KIA lodge, are some pretty fantastic bird pics taken in drizzly weather; no TC used with those, handheld. I really have to get through all the other RAWs, because some of the best shots are still to come; I actually knew how to use my equipment by about 1/2 the trip!

Then there are these pix I took within the first few hours of ownership of the lens...

These were taken just the other week: ( the first 17 only -- first 5 are with the 2X TC )
These were all taken stopped down a good deal, unlike most all the shots taken during my Tanzania outing which were mostly taken at or near wide open.

Criticisms I'd offer are:

- Does suffer from CAs & purple fringing. You can see it in the sun's reflection in the eye of the Dik-Dik below at the very end (last image)... and some bird shots into a gray cloudy sky shows it in the tree branches.

This is wide open. But these type of high contrast situations are pretty much the only time you'll see it. And lets not forget to mention it is the OOF area showing it; few are the lenses of this focal length that don't exhibit color aberrations in the OOF area. So to me, it's acceptable.

Other wide open shots are quite good. Just how good can it get? Have a look here:
and click the original full rez version. Here's a shrunk down version:


(these are with the 1.4x TC) I do note a tad of color fringing in the full rez of these images too. Now that I realized how to use Lightroom correctly, I can/should re-do them to get rid of it.

The pictures I've seen from an A* 300mm f/2.8 recently had even less (though I didn't see 100% crops!). If the FA* are born of the same cloth, that's the hands down winner. But personally, I don't think you'll see new FA* 300mm f/2.8s re-issued, or if you do it'll be priced in the stratosphere, or special factory order only where you have to pay list price... even good condition used ones are $3000 - $3500 today.

- Focuses well enough, but not quite 'ultimate performance' as I wasn't able to catch running gazelles or wildebeests running to or from me too well. It auto focuses much slower when you engage the manual focus ring as well. If you slid the focus rind forward so manual focus is disengaged, it's much faster.

The most frustrating thing I experienced was an incredible bird in the middle of a field. Out of about 10 shots, only two maybe three had critical focus. I couldn't understand what was going on. Happened a few times; mostly with birds. Here's the best of the series:

The series is here: Only about two others come close to that one. Maybe I should go manual focus @ those times.

- I noticed recently when it was snowing the other day, and I was shooting some bird hiding from the snow in the center of an evergreen tree, and it was too dark to autofocus (with the 2x converter), so I went to manual and found the ring was very sticky. I'd have to break it lose go back and forth to get it to go to the right point. Then it would stick again. I don't know... I thought it might be dust within it from my trip. But then I realized it turns freely off the camera and TC ... so I finally just realized it's the TC's gearing that is holding up the manual focus.

- The three aperture screws on the back k-mount ring came loose out there in Tanzania on the rough Landrover. I missed a lot of great shots (one of a single Male lion on a big stone Kopji was a real once-in-my-lifetime shot I missed) as it got so bad the camera couldn't read the lens info from it and gave me a F--- display; I had to crank down and to the right on the camera to force the connection. Once we hit camp a guide had a mini screw driver set and I just had to tighten the screws. I just say it as I read on a few forums of other people experiencing it, so it's not uncommon. I need to give it to Sigma USA to clean the lens out, as it was very lose allowing in air in extremely dusty conditions (Sigma USA in on LI a few miles from my house).

- But in regards to sharpness? Again, picture's worth a 1000 words... This one is f/3.5.

And a 100% 800x800 crop of it... notice the outline of the Landrover with the pop-up roof in the eye of the Dik-Dik. When you consider the image size it came from in the full-frame picture... I'll end with, ya, I have to say it lives up and far exceeds any expectations I had regarding sharpness of it, and the K10D!

(even if I was a bit heavy handed with the sharpening when I first started using Lightroom ... I should re-do this one too!) Again, I think I know how to use Lightroom correctly now to get rid of that ring at the bright edge of the sunlight.

- Ah, something else. Not having a focus limiter is trying sometimes. Especially if you are trying to track a hawk/buzzard/eagle/whatever flying above using auto-focus. If you don't have enough skills to keep the bird in frame, you'll be hearing the lens constantly going from one extreme to the other. If you have the quick-shift focus snapped to manual, and a TC, it's several seconds back and forth. Ouch. No TC, and in purely auto-focus (with the manual focus clutch detached), it's about a second.

- I would definitely buy it again... I have been tempted by some used FA* 300mm lenses I've seen selling for around $3000. If they are as sharp and free of CAs & color fringing as I've seen the A* 300mm to be, it might just be worth the extra several hundred dollars. However this lens works so well with the relatively 'bargan' Sigma 2X and 1.4X TCs, I'd be remiss to give that up and start over with the much more expensive Pentax "long" TCs to match the FA*.

- Also, I find it's OK to handhold without the TC with the proper grip, resting it on my left elbow and left hand holding my right fore-arm / elbow. Can get by with the 1.4x handheld. Challenging with the 2X TC. 2X TC + polarizing filter + handheld is a lesson in futility!

- oh, to re-[re-re-re-etc.]-edit , I found the tripod collar it comes with to be rather 'tiny'; and I was unable to fit my fingers between the mount and lens and carry it around. I therefore felt it neccessary to spring for yet another $180 (I kid you not) to buy the nice big hefty TS-41 tripod collar which doubles fabulously as a handle to carry it around with. :ugh:
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