petrochemist

Joined: 27th February 2010

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petrochemist
No other manufacturers have made K mount DSLRs for quite a while.
I'd second Stu's suggestion of a K5, but think you should be able to track one down for no more than £250.

It might be worth getting a quote for repairing your Kr before deciding what to do.

Comment by petrochemist posted on What other manufacturer bodies take K mount lenses at 31/08/2017 - 00:51

petrochemist
I keep looking but recent boot sales have been quite low on camera gear. I did see 3 tripods last time but all were flimsier than my cheapest backup. I didn't rate them as worth carrying back to the car, so never enquired on the price. A few charity shops in the area sometimes have some nice bits too, but only one has stuff regularly.

The best I've managed to date was a Practica MTL-5 camera & 3 lens kit for £10. The lenses included where a CZJ Tessar 50/2.8, CZJ MC 135/3.5 & CZJ Flektagon 35/2.4 all in good condition. e-bay sold prices suggest the last of these could be worth £200

The runner up is a Tamron model 52BB (SP90 F2.5 macro) for £1. [IIRC it even came with a PK adapter. Admittedly it is in cosmetically poor condition but the optics were reasonably clean & it takes good pictures.]

Comment by petrochemist posted on Used bargains at 30/08/2017 - 14:01

petrochemist
All great shots, and all of species I've yet to see!
TFS

Comment by petrochemist posted on A selection of Dragonflies at 26/08/2017 - 12:59

petrochemist
Puggy wrote:
Very Nice Mike.

Shame it's so close to me but I used all my leave on the BTCC weekends so unable to make it

I like the B-17 best too

Pete A
Thanks just about to leave to grab my spot for today.
I might bump into you on Sunday at Rockingham, I'm taking along a couple of friends from the club.

Comment by petrochemist posted on A few from the Clacton Airshow: at 24/08/2017 - 09:47

petrochemist
Excellent set Pete, MUCH better than any I got.

Comment by petrochemist posted on Knockhill BTCC at 24/08/2017 - 09:44

petrochemist
Gels are often used for control of lighting rather than for imaging through. For lighting the scratches won't make any difference.
If they where sold as lighting gels I'm not convinced you'd have any comeback, if their listing suggests they can be used for imaging then you have good grounds IMO.

Unfortunately they do scratch very easily, or I'm sure they'd be much more popular.

Comment by petrochemist posted on Irix ND Gels at 22/08/2017 - 11:21

petrochemist
2 stops faster than my current 1000mm & MUCH better IQ.
Very tempting except the price is somewhat more than my lens fund has available...

Comment by petrochemist posted on Pentax SMC PK-A ED IF 1200mm f8 Lens at 20/08/2017 - 11:05

petrochemist
bychan wrote:
I've owned a circular 10 stop filter for a couple of years, having only used it once with average results.

So I decided to have another go last weekend, only for my Pentax remote die on me :-/

What I've viewed online, and try, was to compose the scene in AV mode, noting the shutter speed. Then attatch the filter, switch to manual exposure and bulb mode then shoot using a cable release for the appropriate shutter length.

Does this sound about right?
The Pentax remote is being replaced with a wired model.

Thanks
Adrian
I find for normal type 10 stop adjustments it's fairly easy to set the camera up in manual to have suitable settings with out the filter, then fit the filter & simply count stops as you turn the wheels for aperture/ISO/shutter speed adjustments (counting back down if you want to turn one control in the wrong direction) till you get to a total of 10.
This of course falls down if you get beyond 30s, but it's pretty easy to work out from the number remaining.

Rather than using a remote (which I can rarely find when I need it) the cameras 2s self timer is usually adequate.

Comment by petrochemist posted on 10 Stop filter tips at 17/08/2017 - 18:30

petrochemist
Chrism8 wrote:
Hi Rob,

Yes I know, what I was saying is if the exposure is adjusted by 10 seconds there is no real difference to the exposure so if it's 30 seconds or 40 seconds, there's very little visual difference and even less if the initial exposure runs into a minute or more.
That's all very true of really long exposures, as most shots using 10 stoppers are, but not all shots through these filters are long exposures.
Using welding glass that is roughly 18 stops I've photographed the sun & my resultant exposures where small fractions of a second (1/500 springs to mind). Note unlike normal ND filters, welding glass blocks UV & IR as well. Photographing the sun through a normal 10 stop filter will likely result in 'eclipse blindness'... No doubt there will be thousands of cases of this on Monday.
Many less extreme subjects (eg. shallow DOF in bright light) may end up with exposures around 1s, and a 10s difference here will be significant.

Comment by petrochemist posted on 10 Stop filter tips at 17/08/2017 - 18:16

petrochemist
I've played with a few different versions of these . IIRC mine all have a series 7 thread & need a metric to series adapter. Stacking a stepping ring or two could perhaps make issues, but I managed to have a IR filter between the lens & the adapter without any noticeable focus issues.

I did pick up a Raynox wide angle adapter (which clips on small lenses the same way their close up lenses do). It wouldn't focus on anything so I suspect the macro part is missing though there no clear place for it to fit - I only paid £3 & got it for the mounting more than the lens so I'm not really bothered.

Comment by petrochemist posted on K&F fish eye adapter at 15/08/2017 - 19:37

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