[barondla]

Considering a Pentax DA300 f4 or a bigma. How do you think the image quality would compare? What about Pentax with converter vs bigma without? This would be easier if Pentax brought out a longer lens!
thanks
barondla

[little laker]

I have a Sigma 135 - 400, plus I have a old Pentax screwmount 300mm f4.

Since I bought the Pentax lens the Sigma has only made it out once or twice

Although it is coming out for the eclipse tonight, along with a few other long lenses including my 300.

In my opinion the image quality just can't compare, and you'd probably find the same between the 2 lenses your looking at.

I'm not slamming the Sigma's IQ, I just think that Pentax glass is superior.

[afs760bf]

I would think the quality of a DA prime lens would have to give superior results to a zoom such as the Bigma. You have to compromise something making a zoom that long. That's not to say you won't get some good results, but the prime made for the camera would have to be better - IMO, of course.

[Peter Zack]

I think the 300 is going to be better. I really like the Bigma and it's a very good lens but a good prime will genereally outperform even the best zoom. With a good quality TC, you will see some drop in IQ and of course speed but it's not that bad At least IQ wise. So getting the 300 close in FL to the Bigma will result in a slow lens of f5.6+ as well.

Where the Bigma really shines is the vast Focal range it covers for a reasonable dollar. With respect to Stu above. The Bigma is a much better lens than the 135-400. I've owned the Bigma and tried the 135-400. The Bigma wins hands down and is at least equal (if not better) to the older 300m f4 (I had the K mount lens).

So there's the trade off.

I will be getting the Bigma again and only sold it due to some money issues.

[Lowell Goudge]

I presently do not have any lens (except for a 1000mm spotting scope) beyond 400mm, so I can't comment on the BIGMA obviously.

WHat I can comment on however, is that if what you want is 500mm, and only 500mm, that there are better ways to get there.

If you want a zoom, to be practical, I also think there are better ways to get there.

What I have at present is three long options, two of which I use, one which sits on the shelf.

I have a sigma APO 70-200 F2.8 EX zoom, with matching sigma 1.4x and 2x TCs (the 2 x I just reciently purchased, it's real test will be coming in march) I have been extremely pleased with the sigma as a very fast AF zoom, on its own and with the 1.4x TC giving me a 100-300 F4 zoom. With the 70-200 and 1.4x, I am faster at all focal lenghts I can use than the Bigma, to me this is important. I use this with either my *istD or K10D

My second approach is using an old SMC-Pentax 300mm F4 exclusively with the Pentax 1.7x AF TC. This gives me 500mm at only 1/2 stop slower than Bigma. I use this combo almost exclusively with my *istD and AF500FTZ flahs, for wildlife shots. I have posted results previously which are very respectible.

My third option is an old vivitar 400mm F5.6 which is too slow to use with the AF TC, and I think the pentax 300F4 is better even with the AF TC than the Vivitar 400mm without any TC

I believe that if you are only looking to get out to 500mm approximately, the new 300 F4 from pentax and a high quality 1.4-1.7x TC is going to be better than the bigma at 500mm and without the TC you will totally outclass the bigma at 300mm

[TomInJax]

Considering a Pentax DA300 f4 or a bigma. How do you think the image quality would compare? What about Pentax with converter vs bigma without? This would be easier if Pentax brought out a longer lens!
thanks
barondla

Here are two similar photos. Both photos are unretouched, no sharpening, etc. I only resized the first one, and cropped the second of each group. The first is a photo using the Bigma at 500mm, a 100% crop, then a similar photo with the SMC300, then a 100% crop. I like the Bigma better: better contrast, color, and hardly any (none?) fringing compared to the 300.

Note: This comparison is with the Pentax SMC 300 f/4 lens, not the * or DA.

Judge for yourself:

Bigma Full photo (only resized):


100% crop:


SMC 300 Full photo (only resized):


SMC 300 100% crop:

[Lowell Goudge]

Here are two similar photos. Both photos are unretouched, no sharpening, etc. I only resized the first one, and cropped the second of each group. The first is a photo using the Bigma at 500mm, a 100% crop, then a similar photo with the SMC300, then a 100% crop. I like the Bigma better: better contrast, color, and hardly any (none?) fringing compared to the 300.

Note: This comparison is with the Pentax SMC 300 f/4 lens, not the * or DA.

Judge for yourself:

Bigma Full photo (only resized):


100% crop:


SMC 300 Full photo (only resized):


SMC 300 100% crop:

I think this is an unfair comparison, second photo looks to be taken in early spring, low sun and cold ambient light (I note long shadows)

first photo is much later in the year, or much later in the day, with much warmer lighting much higher in the sky (short shadows)

edit note

Went back and looked at EXIF data and seems I am incorrect. Second photo shot 1 week earlier than first.

I do note however, the second photo was shot at 400 ISO not 200, and also slower shutter speed, 1/350 not 1/500. the question is, what about apature. Was the weather different because if weather was the same, the 300 should have been stopped down to F11 to get the same shot. Is this the case? If so, I am surprised. my copy of the 300 is quite sharp and contrasty at this apature.

ALso, note that the K10D will meter incorrectly with the SMC 300 F4 and tend to over expose by about 1 stop.

the mean grey scale is 109 on the 300mm shot and 90 on the bigma shot (this is 1/2 a stop difference in exposure. are you sure it is the lens and not the exposure that gives you the difference?

---

Last edited by Lowell Goudge; 02-21-2008 at 11:03 AM.

[TomInJax]

These photos were taken about a week apart in January 2008. That is the only similar photos that I have. Sorry. A better comparison would be both lenses on the same day at the same place, but I don't have that.

The location is the same, the subject is the same, and the time of day is similar (from what I remember). I don't have the 300 anymore to do a side by side. My overall impression of the bigma vs the SMC300 f/4 is that the Bigma has a LOT better IQ.

Edit: One more detail. These photos were taken from opposite sides of the pen. In the first photo the Lion is looking directly into the light, but in the second photo the sunlight was to his right.

[jgredline]

The Bigma is a much better lens than the 135-400. I've owned the Bigma and tried the 135-400. The Bigma wins hands down and is at least equal (if not better) to the older 300m f4 (I had the K mount lens).

This is really interesting. I read and hear this quite a bit, yet in my own experience I have found that the 135-400APO to be an amazing lens. My Bigma is good too, but at the same focal lengths, I love my 135-400...I am guessing that I have a really good one or a not so good bigma. I am wondering if I should not send my Bigma back to sigma so they can check it out.?

[channeler]

I'm at the point of making the same kind of choices as you barondla. The main contenders I've been looking at are the Bigma, Sigma 100-300 and the new DA 300. I think I'll be opting for the DA 300 as I think IQ should be better than the zoom alternatives, though I'll need to use it with a TC a fair bit to give me the reach I'll want. I'm hoping it will be up to the kind of IQ the older FA* 300 produces which will enable me to get away with using the TC a little more.

Paul

PS: a 400mm would be even better

[simonkit]

Interesting thread for me this one...

I don't use the telephoto end too much but recently bought a "cheap & cheerful" Tamron 70-300 DI LD. Whilst it's good for the money it does suffer some PF & also I'd also like the option of more range.

Whilst I'm sure the prime lenses offer very good IQ surely they are quite limiting regarding composition, not offering the flexibility of a zoom lens

Simon

[Lowell Goudge]

Interesting thread for me this one...

I don't use the telephoto end too much but recently bought a "cheap & cheerful" Tamron 70-300 DI LD. Whilst it's good for the money it does suffer some PF & also I'd also like the option of more range.

Whilst I'm sure the prime lenses offer very good IQ surely they are quite limiting regarding composition, not offering the flexibility of a zoom lens

Simon

Simon

the decision would be different for each user, based upon what is already in his/her bag.

for example, I already own an excellent very fast zoom, the sigma APO 70-200 EX F2.8, plus the 1.4x TC and 2x TC. as a result I am very well covered out to 300mm (at F4). For me, the next logical step is only 500mm, (or a 300mm F2.8 plus a 1.4x TC) not a zoom that gets there. I can put my 2x TC on the 70-200 and get to 400mm F5.6 1/2 stop faster than the bigma and only 100mm shorter.

This is not the same for every one however. Also note that if you have everything else covered up to 300mm reasonably well with a zoom, and you want higher quality at the 300-500mm range, then the 300F4 with a 1.4x TC makes sense over the BIGMA. It really does depend upon what you already own

[barondla]

Interesting arguments. Tend to be a prime guy. tend to distrust Sigma (in the past bought two fairly expensive ones and had trouble with both). Have Pentax A400 5.6 now. It needs some work. When working it is slow to mf. Large # of turns to focus from close to infinity.
Want a hand holdable tele 300+, to shoot birds in flight etc. Ultra highspeed isn't necessary. For that have an Olympus OM 350 2.8, 180 f2 and E300/E330. These lenses are internal focusing and I can do it with one finger. So fast to mf. Problem with Pentax 300 is using converter to get more lens. That won't work with SR! Really hurts hand holding. Pentax has a SR converter on the roadmap but that could be another year away or more.
Sigma seems to be really good IQ and all focal lengths would work with SR. Also allows using tc for greater reach. Strange how the lens has to be zoomed to fit the matched tc properly. Seems to fit the bill, but its a Sigma.
Went through this with the Sigma 180 macro. Finally found a Pentax A*200 macro. That saved me from buying the 180.
It would be perfect if Pentax would bring out a 400 or 500 prime lens of 5.6-8 speed. There aren't many other choices. Don't know of a new 500 prime that matches the bigma in IQ. Depressing.
thanks
barondla

[Richard Day]

I have the FA*300 f4.5 and together with the Tamron 1.4x AF TC is a superb long lens package. I hope (and expect) that the new DA*300 f4.0 will be similar in performance.

For me, the big issue is weight and size. The FA* combo is much smaller and lighter than the Bigma and not only has a much better IQ, but has an extra stop advantage at 300mm and is equal at 420mm (i.e. with the TC). The new DA* looks as though it will be not much bigger or heavier than the FA*, but has an extra 1/3 stop and a larger front filter size as it's f4.0 (77mm) opposed to f4.5 (67mm).

Okay, you don't have the convenience of a zoom, but I find that for the long reaches, i.e. beyond 200-250mm, a prime is not much of a hinderance. For the short to mid tele ranges, I would prefer to use a more compact tele-zoom, such as the anticipated DA*60-250 or the Sigma or Tamron 70-200 f2.8 offerings. Currently I use the cheap but worthy Tamron 70-300 Di LD macro, as a stop gap for the 60-250, and avoid using it beyond 220mm where possible, when the IQ begins to fall away and also gives rise to more PF.

If however, you are fit and strong and want the flexibility of a wide zoom range and are prepared for a degree of IQ loss and massive size compared to the prime, then the Bigma is currently your best option. Personally, I avoid Sigma lenses, I keep trying them out from time to time, but they just don't click with me.

[palmor]

All good arguments for and agaist each setup, and proves that each person has his/her own taste and needs .

Anyway it seems like you want to get to around ~500mm with good IQ. I *think* (since I have no direct exp with either lens) that you'll be able to get the IQ you want with either lens (the 300 with a TC). I bet you can even add a 2x TC to the Pentax and get good IQ and still retain AF in good light.

Ok, if we make this assumption that either lens can produce keepers then you really have to start to look at the other features of each setup and figure out which is more important to you. I guess the 1st question (and maybe it will decide for you) is do you need/want a zoom lens. If it doesn't matter then does weather sealing and SDM focusing matter a lot to you? Do you care about the weight of the Bigma? Is there a big enough cost difference between the two where you live to make the decision for you?

Personally I would wait until I could find a place and compare them side by side. See how fast the 300 focuses with different TC's. See if the weight is an issue, etc. Sometimes just the feel of the lens on the body will be the deciding factor

Not sure if that helps, which ever setup you decide to get don't forget to post some photos with it!


Oh

This would be easier if Pentax brought out a longer lens!

If you really want longer (and have a lot of extra $$) you can always be one of the 1st to get the Sigma 500 f/4.5 or even the Sigma 300 f/2.8 with 2xTC.