Hi Steve and Mike

According to the Sigma site the “DG (DG Lens) these are large-aperture lenses with wide angles and short minimum focusing distances. With an abundance of peripheral illumination, they are ideal lenses for Digital SLR Cameras whilst retaining suitability for traditional 35mm SLRs” their words not mine!

Mike the Photos on your site look impressive. I take it that both of your, are not seeing a noticeable softening at the longer focal lengths? With the 135-400 lens or do you have to come short of the 400mm mark to keep everything sharp?

How is this lens for speed of focus and how noisy is it. As I earlier commented some of my work is done in theatres during a performance and my trusty SMC F 100-300mm usually gets a few disapproving glances when it is grinding away!

Mike I noticed that you are also using 70 –200 f2.8 with a 2x converter. I take it that this was all manual focus as I was under the impression that auto focus wouldn’t work with converter and this lens on a Pentax mount?

Thanks Steve for digging the lens out and looking at the information for me. Pete come mid April if I haven’t made a purchase I could well be contacting you about your lens

Andrzej

Hi

I am looking for some advice for shooting in low light. As mentioned in a posting on another topic I take photos for a local theatre group. I have been using my istD with either a SMC F 100-300 f4.5-5.6 for close up work and for more general shots a SMC 35-70 f3.5-4.5 lens.

I have been saving straight to Jpeg and pushing the ISO up to 1600 on the istD using the spot metering setting. Most of the shots are with the 100-300 lens (with a monopod) with just stage lighting and I think I have got a fair degree of success if a little grainy at times.

I have now up graded to a K20D, not so much for increased pixel count but the CMOS chip giving noise reduction plus the ability to push the ISO much higher and the bonus of image stabilisation and the TAv feature. I expect there is a lot more on the K20D that can help me with so any advice would be gratefully received.

I have been interested in the comments about shooting in RAW or RAW+ in conjunction with checking with the histogram. What sort of pattern should I be looking for on the histogram to maximise the quality of the shots?

I might even give it the monochrome treatment a try as well next time.

Andrzej

Hi Steve

Thanks, at long last I have found it after going through over 1200 Sigma lenses on ebay and going cross-eyed!

It certainly looks interesting and I will keep an eye on it. Is this the same model as yours or do you have the DG version and would I notice the differance?

Andrzej

Thanks Loskeran

I have contacted a shop in my locality and I am waiting a reply as they might have a 120-400 and/or 150-500 in stock for me to have a look at. However, if that falls though I might well take you up on your kind offer.

Andrzej

Thanks for your comments it sounds like the HSM system on the Sigma lenses is just what I am looking for.

I would be interested if anyone has tried the 120-400mm f/4.5-5.6 DG OS HSM (I looked for the 135-400 on ebay but could only see it in a Nikon fit).

I have used a friends Canon EOS D1 mark III with a 100-400 lens and feel confident that 400mm should cover all the situations I need to cover. I have also used my Pentax F100-300 with a 1.7 converter and at the longer focal lengths on one of our normal summer days I just can’t shoot fast enough without a tripod to remove camera shake.

However, one criticism I have seen on Sigma zoom lenses is that they get a little soft at the longer focal lengths. So I am not sure if I should go for the 150-500 and not push the lens so hard or stick with the 120-400 option. The downside with the 150-500 is that the lens would appear to be fractionally slower and for some of the work I do plus the minimum of focal length 150 mm might just be a little long for me.

It would be nice to take my K20D to shop and try both. I live in Cardiff and looking at the local web sites they don’t appear to be carrying any in a Pentax Fit Sigma lenses in these sizes in stock at present.

Hi All

Thanks for taking the time out to give me feed back. I know looking at other posts this seams a popular topic.

I would like some information of the Sigma HSM system in conjunction with the K20D, in that dose it work with the K20D and more importantly what benefits dose it give over a Sigma lens without it. From the literature it would suggest faster quieter focusing. However, if I didn’t have it would I notice it?

I do some work for a local theatre group from time to time, which calls for shooting using only the stage lighting during performances. There are times in crowed auditorium when the Pentax F 100-300mm lens starts hunting I am sure half the audience can hear it grinding away. In some performances I will just go to manual focus, but there are others where I just don’t find it practical. If the HSM system does work as suggested with the K20D in these applications the extra expense would be well worth it.

This was one reason why I was asking about the 100 – 300 F4 as a faster lens would help here, but that we don’t get a choice of HSM for the Pentax fit version. How would this perfume against the Pentax F 100-300 regarding speed of focus and how quiet it is.

Hi All

I have a SMC Pentax - F 100-300 mm f4.5-5.6 lens that lives on my K20D 80% of the time. Ideally I would like to up grade to a 100-400 mm lens as I am always just finding 300 mm a little short. Something a little faster would be nicer to. I do have a 1.7x converter but trying to take hand held shots become really hit and miss.

The Sigma lenses look an obvious choice with the 120-400mm f/4.5-5.6 DG OS HSM and the 100-300mm f/4 EX DG IF HSM with a 1.4 converter when required. Sigma did appear to do an 80-400 as well, which now looks discontinued. However, if this lens works well with the K20D I will try to hunt one down.

A lot of my photography is wildlife and sport and I know there will those out there that would say go for a prime lens but stopping and changing lenses in the elements plus the bad experience of getting dirt on sensors as a result really makes me want to go down the zoom route. Plus I like to be quite minimal when I am out shooting, just camera and lens with a wide-angle lens in my pocket for any moody landscape shots.

I would be grateful on any feedback on the above lenses especial regarding Sigma HSM system with Pentax bodies, is it true HSM will work on the 120-400 but not the 100-300 f4. Are there any other third party lenses out there I should be looking at?