[WestRowOPs]

Remembered I had a loft in my house, whilst up there I found my Camera Case from SLR days (probably unopened since 1998).
I found the following lenses:
Pentax 50mm
Tokina 100-300 Zoom
Pentax 75-150 Zoom
Pentax 100-300 zoom auto focus

Wondering what second-hand DSLR body I could buy to use them all on (Pentax K fittings) for around £150?

not really sure what I am looking for, but seen K-X K-100 bodies in that price range. What are the pitfalls of using manual lenses with a digital camera?

I am only after historical record shots of aircraft (flying and on the ground).

thanks in anticipation

[VoiceOfReason]

If you can spare the money go for a K30/K50 or later to get focus peaking, or if you can live without a OVF a K-01. If you can't then the Kx or Kr would probably be a good choice.

[ChristianRock]

The problem with the K-x and K-r (I own the latter) is that the viewfinder is too small for any useful manual focusing. I am going to sell the K-r and keep the K10D and K-S1. The K-r is otherwise a great camera, especially for the prices they now sell for. The sensor is great IMHO!

[UncleVanya]

The k100d and k100d super have pentamirrors rather than pentaprisms which are a bit darker. The type of focusing screen used in modern dslrs is also not fantastic for manual focus. If you are serious about manual focus some people replace their focusing screen with a split prism or finer matte screen that allows finer focus. If you are lucky you will find a used camera with that and a pentaprism. Look on the site at the camera comparison tool that will help you narrow the search.

[pathdoc]

Ultimately all Pentax DSLRs will work with all older K-mount lenses; that's the joy of Pentax.

Caveats:

1) Manual focus lenses marked PK-A/R or some variant thereof (the R is what's important), and all OEM Ricoh-branded P-series lenses (but not the XR series) have the Ricoh Pin, an essential part of (film-era) Ricoh's auto aperture control system, but the pin coincidentally (and unfortunately) lies in exactly the same place on the mount face where the screw drive shaft protrudes. OEM Ricoh and some high-quality 3rd-party lenses have a rounded end to their pin; others have a square pin that can get stuck in the screwdrive socket and are extraordinarily difficult to remove. Third Party Pentax-compatible AF lenses, naturally, have the screwdrive shaft at that point and are not a problem.

2) Some older lenses which precede the A series have anodised or painted and consequently non-conductive mount faces, which when used with newer Pentax DSLRs will not allow stop-down ("green button") metering. The anodised finish must then be filed or ground off (potentially destructive; hampers resale value) or rendered conductive with a strip of conductive electricians' tape or aluminium foil, where it touches the data pins on the camera. Oddly enough, I think the older DSLRs of the vintage you are nominating are immune to this issue for some reason, but if you got something like a K-5 cheap, this fix would be necessary.

3) Lenses predating the A series do not have electrical contacts and must be metered using the green button; they will as a matter of course not pass aperture data to the camera body nor accept aperture adjustment orders from it (it's all in the aperture ring). Lenses from the pre-autofocus era with electrical contacts (A-type lenses, not to be confused with Sony A mount) will not pass focal length or distortion correction data, and the zooms will thus not reliably pass correct aperture information unless the lens is by nature constant aperture throughout the zoom range. This will affect your exposure.

If you can find a used but functional K-5 series camera within your budget, go for it - for some reason, the sensor in that camera had some real magic put into it and they are a vast improvement in many ways over what came before them (among other things they are weather-resistant, which matters if you choose to invest further in current Pentax lenses). The K-5ii and K-5ii-s are generally accepted as having incremental improvements which make them preferable to a base model K-5 if you don't already have one, but may not be available as cheaply. One of these increments is autofocus, which might make a big difference for some of your ground-to-air shots. IIRC the II-s also lost the anti-aliasing filter and will deliver sharper images (all else being equal) at the slight risk of image moire with repeating patterns.

Then again, others have a definite preference for the colour rendering of the last of the CCD sensors (as opposed to CMOS), and prefer the older bodies which still have them.

Have a look in the camera review database if you need to know more about the specific bodies.

[BigMackCam]

Welcome to the forums

The K-30 and K-50 are nice, but they do have something of a (perhaps exaggerated) reputation for failure of the aperture motor mechanism. I'd probably look at something like the K20D instead. There's a really nice one on eBay UK right now... very good condition, 16,250 shutter actuations (so lots of life left in it), D-BG2 battery grip, two batteries, charger and manual for £164 "Buy It Now", but with the "Make an offer" option... so the seller is obviously looking to get around £150. Given the condition (the photos suggest it's in great shape) and the low shutter count, that's a very good deal.

EDIT: If you can stretch a bit further, I would suggest a K-5 which is considerably newer, and has image quality not terribly different to today's cameras...

[bobbotron]

If you can spare the money go for a K30/K50 or later to get focus peaking, or if you can live without a OVF a K-01. If you can't then the Kx or Kr would probably be a good choice.

Seconded, this is solid advice. A KS1 if you could find one on closeout would be great too.

[pathdoc]

Seconded, this is solid advice. A KS1 if you could find one on closeout would be great too.

The only problem with this advice is that the K-30 and K-50 are known to have an Achilles heel in the shape of the aperture control module. This is prone to failure, sometimes just outside of warranty, requiring a not-inexpensive repair.

On the other hand, I have not heard of the KS-1 failing in the same way. The only issue with the KS-1 is that its ergonomics have not exactly been lauded by some (a matter of taste), and while it is (almost uniquely among Pentax DSLRs of its era) not weather resistant, neither are any of the lenses you are planning to fit to it (both lens and body must be WR for the entire combination to be considered as such).

Last I looked there was one for sale in the forum Marketplace with very few shots on it, essentially new, but the seller is in Australia and postage might be prohibitive for you!

[bobbotron]

The only problem with this advice is that the K-30 and K-50 are known to have an Achilles heel in the shape of the aperture control module. This is prone to failure, sometimes just outside of warranty, requiring a not-inexpensive repair.

On the other hand, I have not heard of the KS-1 failing in the same way. The only issue with the KS-1 is that its ergonomics have not exactly been lauded by some (a matter of taste), and while it is (almost uniquely among Pentax DSLRs of its era) not weather resistant, neither are any of the lenses you are planning to fit to it (both lens and body must be WR for the entire combination to be considered as such).

Last I looked there was one for sale in the forum Marketplace with very few shots on it, essentially new, but the seller is in Australia and postage might be prohibitive for you!

I've often thought the k30 aperture problems are probably overstated. Forums like to latch onto problems; if I were going into this on the cheap, I'd def consider a k30/k50.

(Correct me if I'm wrong!) the KS1 is one of the lightest DSLRs pentax has made, which could be a selling feature.

[TheOneAndOnlyJH]

Remembered I had a loft in my house, whilst up there I found my Camera Case from SLR days (probably unopened since 1998).

Before you buy a body for the lenses, take a good look through them to make sure they're still usable since they've been sitting for so long. If the lenses have issues you might be better off buying a bridge camera or newer pocket camera to stay within your budget.

Lens glass can developed surface defects, especially in humid regions. Minor defects might make your images soft or blurry and add a little glow around highlights, but extreme lens issues could make your pictures into a blurry, foggy, glow. Foggy clouds or spiderweb lines indicate haze or fungus. Basalm separation or coating separation is something else to watch out for. If you only see defects at the edge the lens is still okay to use because smaller apertures only use the center of the lens, and defects in the outer edge will only affect the widest apertures. Some specks of dust are okay, but larger ones near the center can show up at small apertures. Hazy or fungus damaged glass can sometimes be cleaned by someone with skilled hands, but acids caused by the fungus can eventually etch the glass beyond repair.

Also check the aperture blades for oily wetness and flick the aperture lever quite a few times to make sure it snaps shut instantly. Older greases used on focusing helicoids and zoom mechanisms can break down over time and leak into the aperture assembly making it sticky, especially in warm places. A sticky aperture takes longer to close down and might not be fast enough to be ready before the shutter opens, so you could end up with overexposed images at smaller apertures. (A lens with a sticky aperture could still work at wider apertures, but most lenses are softer at their widest apertures.) A frozen aperture that is stuck closed might even damage the aperture actuator lever on the camera. If the aperture looks dry but seems to stick, flick it a few dozen times to see if it helps and then look at it again. Sometimes the spring and hinges will work loose, and other times you'll notice that there was oil that you couldn't see until you work it back and forth. Unlike fungus etched glass, oily apertures are repairable, but it takes a lot of skill and patience to disassemble, clean, and re-grease a lens.

[08amczb]

I have a K-30 with 80'000+ shutter count, no aperture or shutter block problem, so I recommend it too.

[DougieD]

For aircraft in flight I'd shy away from the 6 Mpix cameras such as the K100D. More pixels will help you crop and better noise performance will allow you to turn up the ISO to get the quicker shutter speeds you might need for flying objects.

Just go to Flickr and search for a Pentax model number + "aircraft" to see the pictures people have been getting with the camera you are considering.

[Adam]

Remembered I had a loft in my house, whilst up there I found my Camera Case from SLR days (probably unopened since 1998).
I found the following lenses:
Pentax 50mm
Tokina 100-300 Zoom
Pentax 75-150 Zoom
Pentax 100-300 zoom auto focus

Wondering what second-hand DSLR body I could buy to use them all on (Pentax K fittings) for around £150?

not really sure what I am looking for, but seen K-X K-100 bodies in that price range. What are the pitfalls of using manual lenses with a digital camera?

I am only after historical record shots of aircraft (flying and on the ground).

thanks in anticipation

A used K-30 is probably the best value for the money. A new K-50 was around that price in the US, even, so you might be able to find one in that price range on ebay.

[Penumbra]

There is someone selling a K-r with a KatzEye focusing screen and some extras (magnifying eyecup i think). Check out the marketplace section here on the forums.

[zestoi]

I've used a lot of manual focus glass on my k10d. it's a great body even now if you can stick to iso 400 or under. the k20d has better iso performance from what I've read. either should be around 150quid.

focus peaking on my K50 was great when manually focussing and I've had no issues at all. the k30 is pretty much the same body.