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Modification to add fixed tilt capability to the Pentax SMC 67 55

Modification to be done for adding fixed tilt capability to the Pentax SMC 67 55/4 latest version (not for the faint hearted!)

What you will get with this modification is a Pentax 67 55/4 lens modified in order to have a fixed 0.5-0.8 degrees of downward tilt.
With this mod you will get maximum DoF and acceptable CoC when doing near-far shots (say, from about 1 meter onward, instead of the original 3 meters).
After the mod, the lens won't be able to take "normal" shots anymore. One should devote the lens to vertical near-far type shots only.
The modification is totally reversible.

Disclaimer.
Make this modification only if you are in the right mood and you feel like it.
It is not difficult but you should have a bit of experience and be aware that any warranty will be voided by opening the lens.

I assume no liability for any damage. Your are operating at your own risk!

I want to thanks Mr.Lephing Zha , the inventor of the mod, for his valuable indications and help.
You can admire his work on photo.net, including marvelous landscape shots taken with this modified lens.

	List of tools needed: - A fine tip good quality PH00 screwdriver - Clamps - A clean table

A good screwdriver is the keypoint. If you work with the wrong one, you will screw up everything and won't be able to sell your lens back beacuse of worn-out screws - if not worse! I used a PH-00 swissmade screwdriver. The tip of the tool is hard and fine. I had to buy several screwdrivers before finding the right one. Even if they are all PH00 they are not the same. The wings must fit into the head of the screw perfectly . This is very important as when you loosen the screws you will need to transfer the power of your wrist to the threads, and the tip of the tool MUST NOT slips out of the slots!!!!
	Now remove the indicated screws . Put a bit of downward pressure on the screwdriver before turning it. Once the screws are removed store them away in a safe place . I put them on a sheet of paper maintaing the original layout with the goal of being able to match back each screw with its own original thread during the reassembly stage.
	Raise the cover gently. Be aware that there is an index bracket that is fitted in a slot underneath. Be careful not to bend it.

	Now the work is at a good point. We need to remove another index by removing the two indicated screws. They are blocked by a drop of paint. Be calm and determined when unscrewing them.
	Don't let the screws fall into the barrel, it could be very difficult to recover them!
	Use light clamps to pick them
	Be careful that there are washers underneath. In my case they were glued. Make sure they are fixed and stuck, if they are not it is better to temporarily remove them for the sake of the lens
	Here is the index to let the body know the lens aperture
	Now remove the bayonet. There are six screws to remove.
	It is almost done
	Done!
	Store it away together with the six screws
	Easy isn't it?
	This little strip of teflon will do the trick. The thickness is about 1 mm. Do not use too much otherwise the index will hit the slot on the bayonet and auto-indexing won't work properly anymore. This little shim will bring 0.5-0.7 degree of tilt, enough to improve DOF a great deal.
	Here you can see how to fit the strip
	Be careful in choosing which pair of screws you want to put the teflon shim on. You want to have a fixed downward tilt that works in vertical shots only. Take in account which side you tilt the camera when doing vertical shots on a tripod.
	From this point on, you have to reverse the procedure seen to get your lens operational again. Pay attention when introducing the black cover , fit the long index accurately into the slot.
	Very important!
	The modification is reversible at any time with no visible sign . Enjoy the Scheimpflug rule in the P67 world!