Re: A* 600/5.6 question
Well, the jury is still out. It was so hot today that I could see heat waves in zoomed in live view. I will try again later. I suppose I might not have let the lens warm up enough, but the test target is across the street and the pavement was kicking up tidal waves. Anyway, I couldn't tell if any sharpness differences were from the filter, lack of the filter, or heat distortion. I dug through half a dozen Ilford paper boxes looking for anything that resembled a decent quality 49mm UV filter. I found something called a Ghostless UV filter, and one called Cloudy, which appears to be a slight warming filter. Both Pentax brand. They will do for my purposes. bill -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
On Mon, Jun 28, 2021 at 08:13:19PM -0600, Bill wrote: > > My A* 600/5.6 (I like being able to say that) came with a huge Tamron clear > filter. Probably a UV. It was a sharpness killer. I took it off and the > lens is a lot better. > I suppose I should toss a filter into the drawer and see what happens. > > Bill I've got a couple of lenses (A* 300/2.8, FA* 250-600/5.6) that have the filter holders. Somehow my little sleeve of filters for the 250-600 got lost fairly early on (probably at a race weekend), so for most of my shots with that lens there's been nothing in the filter holder. I keep telling myself to see if I can get a compatible filter to mount there. I can't say I've noticed any degradation. There again most of the time I'm using that lens on a monopod to track moving targets, so it hasn't had an absolutely rigid platform. -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
Every lens I’ve had that had a filter tray or internal filter mount like this has required a matched thickness filter in the tray to achieve their best performance. Even my Sigma 600mm reflex does. G > On Jun 28, 2021, at 3:19 PM, Mark C wrote: > > On 6/28/2021 1:49 AM, David Mann wrote: >>> On Jun 28, 2021, at 5:22 PM, jtainter wrote: >>> >>> Bill wrote: >>> >>> "Does anyone know if the above mentioned lens needs a filter in the filter >>> drawer to achieve it's maximum magic? >>> "Thanks" >>> >>> Bill, the F* and FA* 600 F4 lenses do require a filter as part of the >>> optical system. I would therefore suspect that the A* 600 does also. >> I just had a look at the optical diagrams on the K-Mount Page. The F / FA >> optical diagram shows the filter as part of the optics but the A* 600/5.6 >> doesn't. I certainly wouldn't take that as gospel as I don't know where >> those diagrams come from. I'd tend to assume that any lens with a filter >> drawer would need the filter. Clear as mud :D >> >> Cheers, >> Dave >> -- > > Interesting note about the optical diagram. I've had the question about > filters on the A* 400 f2.8 and its optical diagram does show a filter in > place. never thought to check that. I always used a UV filter with that lens > but wondered if it was really needed. > > Mark > -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
On Mon., Jun. 28, 2021, 4:19 p.m. Mark C, wrote: > On 6/28/2021 1:49 AM, David Mann wrote: > > On Jun 28, 2021, at 5:22 PM, jtainter wrote: > > > >> Bill wrote: > >> > >> "Does anyone know if the above mentioned lens needs a filter in the > filter drawer to achieve it's maximum magic? > >> "Thanks" > >> > >> Bill, the F* and FA* 600 F4 lenses do require a filter as part of the > optical system. I would therefore suspect that the A* 600 does also. > > I just had a look at the optical diagrams on the K-Mount Page. The F / > FA optical diagram shows the filter as part of the optics but the A* > 600/5.6 doesn't. I certainly wouldn't take that as gospel as I don't know > where those diagrams come from. I'd tend to assume that any lens with a > filter drawer would need the filter. Clear as mud :D > > > > Cheers, > > Dave > > -- > > Interesting note about the optical diagram. I've had the question > about filters on the A* 400 f2.8 and its optical diagram does show a > filter in place. never thought to check that. I always used a UV filter > with that lens but wondered if it was really needed. > > Mark > -- > My A* 600/5.6 (I like being able to say that) came with a huge Tamron clear filter. Probably a UV. It was a sharpness killer. I took it off and the lens is a lot better. I suppose I should toss a filter into the drawer and see what happens. Bill > -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
On 6/28/2021 1:49 AM, David Mann wrote: On Jun 28, 2021, at 5:22 PM, jtainter wrote: Bill wrote: "Does anyone know if the above mentioned lens needs a filter in the filter drawer to achieve it's maximum magic? "Thanks" Bill, the F* and FA* 600 F4 lenses do require a filter as part of the optical system. I would therefore suspect that the A* 600 does also. I just had a look at the optical diagrams on the K-Mount Page. The F / FA optical diagram shows the filter as part of the optics but the A* 600/5.6 doesn't. I certainly wouldn't take that as gospel as I don't know where those diagrams come from. I'd tend to assume that any lens with a filter drawer would need the filter. Clear as mud :D Cheers, Dave -- Interesting note about the optical diagram. I've had the question about filters on the A* 400 f2.8 and its optical diagram does show a filter in place. never thought to check that. I always used a UV filter with that lens but wondered if it was really needed. Mark -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
On Jun 28, 2021, at 5:22 PM, jtainter wrote: > Bill wrote: > > "Does anyone know if the above mentioned lens needs a filter in the filter > drawer to achieve it's maximum magic? > "Thanks" > > Bill, the F* and FA* 600 F4 lenses do require a filter as part of the optical > system. I would therefore suspect that the A* 600 does also. I just had a look at the optical diagrams on the K-Mount Page. The F / FA optical diagram shows the filter as part of the optics but the A* 600/5.6 doesn't. I certainly wouldn't take that as gospel as I don't know where those diagrams come from. I'd tend to assume that any lens with a filter drawer would need the filter. Clear as mud :D Cheers, Dave -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: A* 600/5.6 question
Bill wrote: "Does anyone know if the above mentioned lens needs a filter in the filter drawer to achieve it's maximum magic? "Thanks" Bill, the F* and FA* 600 F4 lenses do require a filter as part of the optical system. I would therefore suspect that the A* 600 does also. Joe -- %(real_name)s Pentax-Discuss Mail List To unsubscribe send an email to pdml-le...@pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
