Forgot Password
Pentax Camera Forums Home
 

Showing results 1 to 25 of 300 Search:
Forum: Pentax SLR Lens Discussion 1 Hour Ago  
[?] Lens identification, Noname/Seikanon 28-80mm F3.5-4.5, ca. 1980
Posted By Lowell Goudge
Replies: 1
Views: 119
Try this

SEIKANON Trademark of KITS CAMERAS, INC. Serial Number: 73408485 :: Trademarkia Trademarks

One of many store brands in the late 70’s and early 80’s
Forum: General Talk 03-26-2020, 04:19 AM  
Coronavirus
Posted By Lowell Goudge
Replies: 1,505
Views: 29,548
Sadly it is an under reaction. We should have adapted social distancing and isolation once the first case was observed outside of China.


The reason there is a lockdown now is primarily because it was not taken seriously enough at the onset.

We, as a society (specifically in North America) had what appears to be arrogance, in that we thought we could trace every possible infection vector and therefore naively through the could control the outbreak.

Even look at our repatriation of our population abroad. It is law for them to self isolate now, but only after travelling internal to the country unchecked, until they get to their true home. They should be quarantined at airport hotels, adjacent to where they arrive, but no, we donít want to do that, so we are bring a second wave in before the first is controlled.

The real problem is no one wants to take drastic measures at the onset, they always believe they can postpone the issue, but in doing so, it just ensures a much larger issue later


Like I said, arrogance
Forum: General Photography 03-26-2020, 04:01 AM  
DIY Gear
Posted By Lowell Goudge
Replies: 65
Views: 3,626
Have you considered interpgrating a tripod mount into the rear part. That is a lot of load cantilevered off the camera body tripod mount
Forum: Post Your Photos! 03-23-2020, 06:00 PM  
Pets Jillian - Socially Isolating Again
Posted By Lowell Goudge
Replies: 7
Views: 262
A politically correct retriever? Impossible:lol:
Forum: Lens Sample Photo Archive 03-22-2020, 02:22 PM  
Sticky: Index of lenses in this section
Posted By Lowell Goudge
Replies: 32
Views: 53,388
Seems to work on my iPad
Forum: Post Your Photos! 03-21-2020, 01:27 PM  
Nature Handsome Young Cooper's Hawk!
Posted By Lowell Goudge
Replies: 16
Views: 435
You know the coopers are happy when you go outside and think itís snowing, only to discover itís down feathers coming down:lol:

I have found several times in my yard simply a circle of feathers. At one point for a period of 2 weeks you could set your watch based upon when they would visit the yard. It seems they almost have a programmed route, and as long as they find food they keep coming. My experience is they prefer doves. I donít get doves any more...
Forum: Lens Sample Photo Archive 03-21-2020, 03:56 AM  
SMC Pentax 135-600mm F6.7
Posted By Lowell Goudge
Replies: 22
Views: 820
I would be really curious to compare this lens against the tampon SP 200-500/5.6 that I have.

It suffers all the same issues, specifically the tripod mount is way too far back to balance. Did you experience any purple fringing? How much did you have to do in post processing?

I like your shots. I have read that this lens has a fairly long minimum focusing distance, was that giving you trouble? It is one reason I got the Tammy, it focuses to about 10 feet (at 500mm) it is really goofed for the little birds
Forum: Post Your Photos! 03-21-2020, 03:39 AM  
Nature Chickadee crashes a lens test.
Posted By Lowell Goudge
Replies: 10
Views: 494
You were looking for 5+ stops from the IS system, I have done that a couple of times, but canít do it regularly
Forum: Post Your Photos! 03-16-2020, 04:14 PM  
Abstract A rare fly over
Posted By Lowell Goudge
Replies: 0
Views: 167
Not the best shot, as I was trying to track the falcon against the background, but look what else is in the frame

I have never seen a peregrine falcon this close to a snowy owl before


Forum: General Talk 03-15-2020, 04:04 PM  
Coronavirus
Posted By Lowell Goudge
Replies: 1,505
Views: 29,548
Its nothing to do with laws, but personal will to interact. :lol::lol: age is a state of mind





QuoteQuote:




---------- Post added 03-15-20 at 03:56 PM ----------


Maybe Lowell could hire you to monitor his place - remotely of course.



No thanks, I have a 90 pound golden retriever to monitor my place thanks
Forum: General Talk 03-15-2020, 03:26 PM  
Coronavirus
Posted By Lowell Goudge
Replies: 1,505
Views: 29,548
You are assuming people will get close enough to have sex
Forum: Pentax SLR Lens Discussion 03-15-2020, 02:33 PM  
Difference between 7 and 8 element Super Takumar
Posted By Lowell Goudge
Replies: 14
Views: 933
Obviously 1 element:lol:

But the 8 element was sharper, but heavier and more expensive to manufacture. The rear element of the 8 element protrudes and is convex, the 7 element rear element is flat
Forum: Pentax SLR Lens Discussion 03-15-2020, 11:28 AM  
Which Rear Converter for SMC K 400mm 1:5.6? 1.4x-S or 1.4x-L?
Posted By Lowell Goudge
Replies: 19
Views: 1,361
To figure this out, look at an older sigma teleconverter sheet. The issue with the 1.4X-L converter is the same as that of the sigma 1.4x and 2X APO teleconverter s. The element protrudes inside the lens barrel.

Any lens that the Pentax X-L converter works on, the Sigma works on also, but the X-L converter sticks even further inside the barrel than the sigma converter
Forum: General Talk 03-15-2020, 05:47 AM  
Coronavirus
Posted By Lowell Goudge
Replies: 1,505
Views: 29,548
I didnít know you could restock common sense. Maybe we can produce boxes containing it:lol:
Forum: General Talk 03-15-2020, 05:15 AM  
Coronavirus
Posted By Lowell Goudge
Replies: 1,505
Views: 29,548
There is a fine line between stockpiling, and hoarding, or worse profiteering from it. The advantage ( so to speak) of a virus over a hurricane, is that normally the water and power and heat will not stop. And essential food delivery will not stop. So you really only need 2-3 weeks of food to be able to self isolate.

Common sense has absolutely nothing to do with the behaviour we are seeing.

---------- Post added 03-15-20 at 08:16 AM ----------







Just buy flour sugar, etc, and not cakes and biscuits. You will be so busy baking you will forget to eat:lol:
Forum: Post Your Photos! 03-14-2020, 05:23 AM  
Nature Handsome Young Cooper's Hawk!
Posted By Lowell Goudge
Replies: 16
Views: 435
Nice shot, I have found that feeding small birds generally draws these guys. The ones in my yard are bold enough to sit on the feeder.

I would be curious to see him in your BIF shots, but he probably fills the frame:lol:
Forum: Pentax SLR Lens Discussion 03-11-2020, 06:36 PM  
Lens bokeh ability
Posted By Lowell Goudge
Replies: 40
Views: 1,207
I have often maintained that it is the relative magnification of two lenses with respect to the ratio of focal distance to background out of focus that matters. For the same subject size, you are closer with shorter lenses, for the same image size, and this changes the perspective and size of the background with respect to sjuject, so longer lenses make bigger blurrier blobs than shorter lenses that reduce things to a confusing mesh of small spots
Forum: Troubleshooting and Beginner Help 02-24-2020, 10:34 AM  
M42 Enlarger Lens adaptaer help?
Posted By Lowell Goudge
Replies: 11
Views: 599
There is an m42 focusing helix that Pentax made, if you have the right length extension tube plus focusing helix, you would be all set.
Forum: Post Your Photos! 02-23-2020, 05:28 AM  
Abstract Checkmate
Posted By Lowell Goudge
Replies: 5
Views: 264
But the position of the rook and queen make it stalemate not checkmate
Forum: Repairs and Warranty Service 02-15-2020, 06:19 AM  
Tamron 70-200mm aperture info pin missing
Posted By Lowell Goudge
Replies: 29
Views: 879
Missing that pin is fine, my 28-75 F2.8 XR Di. Is also missing that pin, it tells MF cameras the lens is F2.8 wide open

Try taking the lens in and out of the A position on the aperture ring
Forum: Pentax SLR Lens Discussion 02-11-2020, 06:42 PM  
'Fudging' aperture numbers
Posted By Lowell Goudge
Replies: 31
Views: 1,431
Did a search and found this on lens tests

Popular Photography - Google Books

Read the beginning of the article, “one popular 50/1.4 tested at 53 mm”

I also found depending on the year modern photograph used 5% on focal length and aperture , and at other times had tolerances on focal length that were tightest around 50 mm and the farther away you got on either side from 50 mm the tolerances got wider any where up to 4%.

So in reality it is take it or leave it.
Forum: Pentax Full Frame 02-10-2020, 05:58 PM  
K and M lenses with the K-1. How well does it work out?
Posted By Lowell Goudge
Replies: 32
Views: 1,996
The biggest issue, for me is the lack of flash support. Unless you shoot with A series or later, you give up on through the lens metering (TTL). Since the *istD series Pentax has dropped dual flash support and shifted to only P-TTL that requires to know the native and stop down aperture values for a lens. The Pentax system , like both Nokia and canon, use a pre flash With the lens wide open, to measure the flash vs ambient ratio and then with then calculates the flash needed for the exposure settings based upon the flash GN and set iso, shutter and aperture. While this stops the issue of overexposure in some blended lighting situations, I find the preflash drains the flash batteries much faster, and disturbed wild life much more than classical ttl metering. I wish the flagship lines offered both systems.
Forum: Pentax SLR Lens Discussion 02-10-2020, 04:22 PM  
'Fudging' aperture numbers
Posted By Lowell Goudge
Replies: 31
Views: 1,431
No I was careful in my statements that I measured the actual diameter of the lens itself, as opposed to using the nominal filter diameter.

---------- Post added 02-10-20 at 06:30 PM ----------



I think this is true only i one sense, the front element diameter can be larger than the entry pupil diameter, and this is often the case on wide angles lenses, but it can’t be physically smaller as far as I know

Edit note:

I should probably reword my last comment slightly to something along the lines of the ratio of front element to entry pupil diameter with respect to the magnification of the front element / group. But at the end of the day, You cannot take in more light than the diameter of the front element.
Forum: Pentax SLR Lens Discussion 02-10-2020, 08:16 AM  
'Fudging' aperture numbers
Posted By Lowell Goudge
Replies: 31
Views: 1,431
i think the real answer is very simple. within all lens specifications there are tolerances on both focal length and aperture. in the good old days when photo magazines were somewhat independent of manufacturers. you would see lens test reports showing the focal length and aperture of the lenses as received. what we are discussing here is either a 1/6 of a stop error in aperture, or perhaps the lens only has 192mm focal length, both probably within the limits of standard lens nomenclature.

as an example, my vivitar 70-210/3.5 version 1 which is a well regarded lens, has a front element diameter, inside the beauty ring of 55 mm which would make it F3.8 even my nikon 300/4.5 which inside the lens retention ring measures 62mm in diameter works out to f4.8 clearly at the time this seems to be a common practice

note, i found some old Popular photography reports on line, and what i noticed is normal to wide angle lenses seem to be Longer than stated but by the time you get to medium tele to tele, they are shorter than stated. just a quick observation not sure if it is true for all lenses.
Forum: Pentax SLR Lens Discussion 02-09-2020, 06:09 AM  
Pentax Smc 300 f 4
Posted By Lowell Goudge
Replies: 10
Views: 571
In looking at the posts in total, the op wants a medium tele, and does not want to use his 500 /4.5 any more. (He can sell that to me :lol:) 300mm would do the trick, but for the money he would get from the sigma, the da300/4 wound seem logical. The K300 for 50 is a good price, just to play and see if he likes the focal length
Search took 0.05 seconds | Showing results 1 to 25 of 300

 
Forum Jump


All times are GMT -7. The time now is 12:36 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top