[sergysergy]

Those are pretty good options, especially in terms of IQ. Sigma have had nice TCs, matched to their lenses. However, the lenses do not appear to be available new anymore. Also, while HSM can be close to screw drive in terms of speed, the motors can get dirty resulting in much slower operation until cleaned (not by user). For motorsports, I think the Tamron is a better option. Optics are quite good, and the lens is considered solid (not always so with Tamron).

I had the non HSM versions and were quite good with the K-5. Unfortunately I never had a chance to use them with my K3, which I assume would be better

[reeftool]

I'm currently using the Sigma 150-500 on my K5 for motorcycle racing. A shorter zoom like the DA 60-250 would be excellent IF you don't need the reach. For flat track dirt racing and winter ice racing, I prefer the Sigma because I need to keep my distance from the clouds of dust and in the winter, snow and ice. I generally use the Sigma mounted on a tripod and position myself on a turn. For motocross, the Sigma is just too big. I can get much closer and there isn't the dust since they water the course around the jumps, where I usually shoot. I also have to hand hold at the motocross and my focal lengths are usually around 100-150mm.

For myself, I need a long zoom and a mid length to cover what I'm currently shooting. The Sigma is a big heavy beast that I have difficulty hand holding even on the short end of the zoom but some of the races where I shoot, I need every MM of the Sigma.

[osv]

I'm thinking now if the 150-500 would perform better with the K3 body, or should I go with Pentax 60-250 f4, or maybe 300 f4. In this period I realised I do need flexible Len (not fixed) so I'm more toward the 60-250 with eventual tc (1.4).

i would not plan on depending on a tc for any job where af accuracy is critical.

like those bike pics, wish that i had the opportunity to shoot 'em out here.

[gastch]

I used to shoot ALMS races. I have not done so in a long time. I was just pondering the same issue just a few days ago. If I had to shoot motorsports today and wanted to use Pentax bodies to do it my lens options would be as follows in order of cost (cheapest to most expensive):

1. Sigma 150-600 (C) - $1050 (lens) + $400 lens conversion to K-mount form Sigma - Total cost: $1,450
2. Pentax 150-450 - Approx. $1,900
3. Sigma 150-600 (S) - $1,920 + $400 lens conversion to K-mount from Sigma - Total Cost $2,320

I just checked yesterday, Sigma is offering mount conversion for select lenses. For the long lenses it is $250 plus shipping cost to Japan. Sigmas would have a four-year warranty compared to Pentax's one-year.

BTW, I have tried the 60-250 in a few camera shows. The focusing was way too slow for me. I think for sport shooting it may come up short. I have read a lot of positive reviews on the 60-250 sharpness. The copies of the 60-250 I tried were not that sharp wide-open, perhaps bad copies.

I'm interested in the lens mount conversion. Do you have more information or a link. From my understanding from my email conversation with a Sigma the lens has to have been originally available in k-mount. See a link below to a conversation I had with Sigma. I would get a 150-600 if it could be converted.

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/292207-emai...tax-mount.html

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Last edited by gastch; 10-04-2015 at 12:58 PM.

[btnapa]

I'm interested in the lens mount conversion. Do you have more information or a link. From my understanding from my email conversation with a Sigma the lens has to have been originally available in k-mount. See a link below to a conversation I had with Sigma. I would get a 150-600 if it could be converted.

https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/292207-emai...tax-mount.html

The information is on Sigma's site. I was under the same impression as you regarding the lens being available for K-mount originally. But according to their site if the lens is convertible then they can convert it to any of the listed mounts on their site. And K-mount is one of the listed mounts for conversion. I will recommend that you call them directly and get the word directly from Sigma service.

[GixxerMKD]

I've ordered the K-3 today (Adorama deal: body + 50 f/1.8) and i still have the 18-55 from my previous kit. At the moment i can find only used Sigma 150-500 (800$) on Amazon, and the Pentax DA 300mm F/4 is around the same price, so again, i have to think this over... From one side i want to go with the 300 because it's weather sealed (and i do shooting in dust and rain, especially on motocross races), and from my experience so far i won't have problem with the end reach. Previous lens i was using lengths over 300, but it was not because i wasn't able to come closer, what i'm saying is even thou it's good to have the coverage it's not so necessary. Anyway, my issue is that i'm going to miss more the range from 55-300, so perhaps 55-300 WR + DA 300 would do the trick... I wish i had a chance to try the DA 300, that way i'd know if i should stick with the 150-500 or go with the prime...

[audiobomber]

I wish i had a chance to try the DA 300, that way i'd know if i should stick with the 150-500 or go with the prime...

I had the 150-500 and have a DA*300 with Pentax TC. The Pentax has far superior IQ. AF speed is about even without the TC.

[gastch]

The information is on Sigma's site. I was under the same impression as you regarding the lens being available for K-mount originally. But according to their site if the lens is convertible then they can convert it to any of the listed mounts on their site. And K-mount is one of the listed mounts for conversion. I will recommend that you call them directly and get the word directly from Sigma service.

I contacted Sigma and as I thought you can't get a mount conversion on a lens that has not yet be released in Pentax mount. It's actually very clear on their website so I'm not sure what you are reading.

[btnapa]

I contacted Sigma and as I thought you can't get a mount conversion on a lens that has not yet be released in Pentax mount. It's actually very clear on their website so I'm not sure what you are reading.

Thank you for clarifying. In that case the choices are much more limited.

[GixxerMKD]

Since my options are limited regarding the new Sigma 150-500, and the Pentax-D FA 150-450mm is out of my budget, i started thinking about getting manual focus lens.... anyone here tried one of those Pentax / Takumar / Vivitar / Riconar etc. telephoto lens for motorsport? If so, what should i look for?

[charchri4]

If the new Pentax 150-450 was half the price this would be a no brainer. Anyone know if there is a head to head comparison between the Sigma 50-500mm (or 150-500) and the Pentax HD DA 55-300mm f/4-5.8 ED WR?

I just bought a 55-300 and like the speed and price but I wish I had more reach. I'm considering returning it for a Sigma but at 3x the cost it's a big jump. This is a shot at 300mm


But this is what I usually shoot...

[Conqueror]

Pentax-D FA 150-450mm is out of my budget

Can you find a way of holding out for it... or some other way of getting it?

LBA is a cruel beast... you might end up lusting it and wanting it... to avoid that no compromise can be made, buy once not twice

[GixxerMKD]

At the end from so much thinking and choosing i've ended up with Tamron AF 70-200mm F/2,8 LD Di MACRO. Can anyone suggest me what will be good teleconverter to use with it on the K-3?

[clackers]

At the end from so much thinking and choosing i've ended up with Tamron AF 70-200mm F/2,8 LD Di MACRO. Can anyone suggest me what will be good teleconverter to use with it on the K-3?

I use the Pentax 1.4.

[clackers]

For motorbike racing this Pentax pro prefers the older screwdriven FA*400 and FA*250-600:


https://www.ephotozine.com/article/shooting-motorsport-with-the-pentax-k-30-22663