Frequently Asked Questions about the Bonfoton Camera Obscura devices.


  • I have never heard of Camera Obscura, what is it?

  • Well, if you walk into a very dark room on a bright day and make a small hole to the window cover and look at the opposite wall you will see the scene outside the window transferred to the wall, only upside down! 

    The words Camera Obscura comes from latin:

    Camera = Room / Obscura = Dark

    This phenomenon can be explained by a simple law of physics. Sunlight travels in a straight lines and when some of the sun’s rays reflected from a bright object (like the tree on the drawing below) pass through a small hole in a thin material the direction of the rays do not scatter, but cross and reform as an upside down image on a surface parallel to the hole.


    This Camera obscura diagram shows how the Camera obscura image is formed by sunlight reflecting from a tree outside the darkened room.


    Using the Bonfoton Camera Obscura Room lens you can make that small hole larger which allows more light to enter the room and the image will become much brighter and sharper!

    And by using the BonfotonUP device, the image will be RIGHT-SIDE-UP / Flipped!


    Can I use the Bonfoton Camera Obscura devices in any room with a window?

    Yes, but keep in mind, that the distance of the object reflected from outside (like a tree) is relative to the distance where the sharpest image appears inside the room.

    See the charts below for detail. The X-axis shows the different object (like that tree mentioned before) distances outside and Y-axis/curve shows the distance from the lens/prism where the sharpest image will appear inside the room.


    To make things a bit simpler, think of it like this. The closer the tree is, the further the sharpest image of that tree is pushed inside the room. The image will appear in the room at any distance, just the image sharpness will gradually soften as further it goes from the focus point.

    The BonfotonUP Kit includes two lenses with focal lengths 4000mm and 3200mm. The Bonfoton Camera obscura Room lens is a 4000mm lens. 
    Other focal lengths can be obtained by request.

    Can you tell more about the BonfotonUP and how does it work?

    Sure! The BonfotonUP is an optomechanical device made of a CNC-milled aluminum frame with a black anodized finish. It has a thumbscrew operated tilt mechanism for adjusting the image vertically on the wall. It has a strong suction cup for direct window attaching and a bottom-mounted adapter for using solely with a tripod. The optical system consists of two switchable lenses, a 4000mm and a 3200mm lens for enabling usage in different room sizes (See the charts above), and a large 400g / 140oz high-quality optical-grade glass prism.

    The flow of light through the optical system: As the first optical element the Lens produces an inverted image, then the light propagated along the longitudinal axis of the prism is inverted for the second time by 180° thus creating a clear and colourful UP right / flipped / rotated image! 

    The overall weight of the BonfotonUP is 825g / 29.1oz and dimensions are: Width 75mm / 2.95in, length 135mm / 5.31in and top height 155mm / 6.1in. The bonfotonUP comes packed in a luxurious black box with a velvet lining. In addition to the BonfotonUP device, the box includes the user manual, the second lens, security rope assembly, microfibre cloth, and a hole cutting template.

  • How do I install the Bonfoton lens or the BonfotonUP?

  • The Bonfoton Camera Obscura Room Lens and the BonfotonUP have different window attaching options. Both devices come with their own User manuals with detailed installing instructions and other handy tips for making Camera Obscura rooms.

     - How to install the Bonfoton Camera Obscura Room Lens 

    The Bonfoton Room Lens is easy to install. In the composite image below, the stages of the installation to a Blackout roller blind are seen.

    Images 1. and 2. Use the logo sticker to draw a right size circle.

    Image 3. Cut a hole in the canvas (or other material you are using for room darkening).

    Images 4. and 5. On the backside of the Bonfoton Room Lens, there are four small metal plates with adhesive. Peel off the adhesive liners from the plates and press the Bonfoton Room Lens over the hole. When you remove the Bonfoton Room Lens the plates will be stuck onto the canvas. The Bonfoton Room Lens has magnets on the back so it can be reattached to the plates. The blackout roller blind can still be rolled back up normally. The small metal plates will just roll inside the blind.

    Image 6. The Bonfoton Room Lens comes with a Blackout Cover Plate that snaps onto the front magnets. The Blackout Cover Plate can be used to darken the room again when needed.





    Before cutting a hole to a Blackout roller blind you might want to test which is the best position for the Bonfoton Room Lens. A rule of thumb for the lens positioning: The higher the Bonfoton Room Lens is on the window the more sky you will get on your walls and the lower the Lens is, the more ground will be seen.

    The quickest room darkening method: The Tinfoil!

    Lightly spray the window screen with water and spread the tin foil roll over it. You can roll the tin foil over the frames of the window so no light will come through from the sides. Don't leave the tin foil on the window screen for too long. The drying water might leave stains that are hard to clean. In hot climate this can happen in a day.


     - BonfotonUP installing

    There are two main ways to install BonfotonUP. Using the suction cup and using the tripod mount. The BonfotonUP comes with a User Manual with detailed instructions. Here are the main steps using the suction cup.

    Here's a quick HOW-TO-USE Video.

    1. Darken the window. There are many different ways to darken a window, but I’ll describe the aluminum foil method here. (See more room darkening tips here).

    Lightly spray water onto the window screen. At this point decide the BonfotonUP attachment position. It’s better to install the BonfotonUP to the center of the window that on the side, as the window frame can obstruct the image side. Remember you can adjust the image vertically with the BonfotonUP! 

    Place the Hole cutting template UNDER the foil to the decided position. Then, with your fingernail or another sharp object, cut the foil by tracing around the hole cutting template under the aluminum foil. (Note, when using aluminum foil, you should not leave it on the window for too long, especially in hot climates, as the water can leave hard to remove stains to the window screen)

    1. Use the Microfiber cloth provided to clean the window screen seen on the hole just made. Make sure the suction cup is clean too.
    1. Attach the BonfotonUP by placing it against the window over the hole. Press suction cup firmly against the window and lift the suction cup handle up. (With old or brittle windows, you should use the tripod attachment option described below)
    BonfotonUP Camera Obscura Device installing1 


    1. Adjusting the image: Loosen the thumbscrew whilst holding the prism head with your other hand. Adjust accordingly by tilting the head. (The thumbscrew can be attached to both sides of the BonfotonUP).


    BonfotonUP Camera Obscura Image Adjustment
    1. Changing the lens: Detach the thumbscrew fully and lower the prism head to the lowest position. Now the lens and the lens roof plate can be removed and a new lens can be inserted. 
    1. Window attaching with a tripod: On the bottom of the BonfotonUP is a standard mount for a ¼”-20 UNC tripod screw. Attach the BonfotonUP to the tripod and lean it against the window.
  • How do I darken my room and does it have to be completely dark?

  • You’re in luck since we have a whole page dedicated just to room darkening tips and tricks!

    How to darken your room for Bonfoton Camera Obscura Device - link

    No, the room doesn’t have to be completely dark. The Bonfoton Camera Obscura Room Lens and the BonfotonUP can withstand quite a bit of stray light. But the image will look brighter and more colourful if the room is completely dark. 

    Note! The Bonfoton Camera Obscura Devices need sunlight (but not direct sunlight) to make the best image on your walls. On full cast days, the image is dim. 


  • I can make a pinhole camera without a lens so, can I make a Camera Obscura room also without a lens?

  • Sure, you can, but the image formed by the small hole will be blurred and very dark. The Bonfoton Camera Obscura devices are specifically designed to overcome this problem! Using the Bonfoton Camera Obscura devices the image formed on the wall will be much sharper and brighter. (And Right-Side-up with the BonfotonUP!)


  • Is it safe to shop on your site?

  • Yes. We understand that the safety of your personal information is extremely important to you. To protect your personal data and credit card information from unauthorized access Bonfoton.com uses Secure Sockets Layer (SSL) technology to provide you with the safest, most secure shopping experience possible. SSL technology enables encryption (scrambling) of sensitive information, including passwords and credit card numbers, during your online transactions.
    All of the forms on our site are secured with SSL technology so your personal information stays safe and out of malicious hands.


  • What is your ordering process?

  • Our order process is very simple – once you make your purchase through the checkout, you will receive anOrder confirmed -emailand as soon as we dispatch your order, we will send you aYour order is on the way -emailto let you know it’s on its way.


  • What forms of payment do you accept?

  • We are happy to accept Paypal, Apple Pay & most major credit cards such as Visa, MasterCard and American Express.


  • I can change the currency on the website, but I can only use US Dollars in checkout why is this?

  • The popular Shopify eCommerce platform that we are using as our storefront only enables us to use only one default currency at checkout. Sorry about that. But don't worry you can see the prices with different currencies on our storefront which are just converted at checkout to US dollars.


    Do you provide any discounts? 

    Yes! We have a default -20% discount for people in the educational sector such as students and teachers. The discount code can be obtained by request. We also provide occasional discounts which are seen on the webpage. 

    Note. During the Black Friday Sale other discount codes are disabled. 



    Shipping is FREE on all orders worldwide and all orders are shipped from Turku, Finland, where they are manufactured.

    We use two different shipping methods.

    1. The BonfotonUP is shipped using the fast and tracked FedEx International Priority shipping.
    2. For the Bonfoton Camera Obscura Room Lens we use the Finnish Postal Service (Posti) to deliver the Lens straight to your mailbox. The Bonfoton Camera Obscura Room Lens fits in an A5 size letter. Note, that if you order two or more items they will be shipped as individual product letters. Also, note that this shipping method does not include tracking.
    3. Note. There is a Shipping Upgrade option for the Bonfoton Camera Obscura Room Lens too with a same flat price globally. Using the FedEx International Priority Shipping method. 

    Your order will be sent out as soon as possible after we have received your payment. You will receive an Order confirmed -email first to your inbox.

    Next, you will receive a Your order is on the way -email after we have shipped your order.

    If you haven’t received the emails, please check your spam inbox


    Below are the FedExInternational Priorityshipping times(free for BonfotonUP) after pickup from the Bonfoton Office (Times provided by FedEx) for different continents:

    Europe: Noon next day or the end of the business day 

    United States: Next day 3:00 PM or after two days until 10:30 AM

    Canada: 2 days until noon

    Latin America: 3 days to largest business centers

    Asia – India – Middle East: 2 days to largest business centers

    Africa – Oceania: 2-4 to largest business centers 

    Note, the FedEx courier will call you in advance to the phone number provided in the checkout to confirm you are present in the address to receive the package.


    Bonfoton Camera Obscura Room Lens 

    Here are the approximate shipping dates using the Finnish Postal Service POSTI (Free for Bonfoton Camera Obscura Room Lens) (Times provided by the Finnish Postal Service) for different continents:

    Scandinavia and Central Europe: 2 - 5 working days

    The rest of Europe: 3 - 6 working days

    Rest of the World: 7 - 20 working days


    Note. Because of the COVID-19 pandemic there have been shipping delays when using the Finnish Postal Service POSTI shipping method. 


    There is also a Shipping Upgrade option for the Bonfoton Camera Obscura Room Lens too with a same flat price globally. Using the FedEx International Priority Shipping method. 


  • Can I track my order?

  • When using FedEx (Free for BonfotonUP): Yes. The tracking number will be emailed to you automatically. Here’s a link to the FedEx tracking site:
    FedEx® Tracking

    When using the Finnish Postal Service POSTI (Free for Bonfoton Camera Obscura Room Lens): Tracking is not included in the POSTI shipping method. Sorry about that.

    Note. There is a Shipping Upgrade option for the Bonfoton Camera Obscura Room Lens too with a same flat price globally. Using the FedEx International Priority Shipping method. This option includes tracking.

  • Will I have to pay international taxes & duties?

  • If you are ordering within the EU you will not need to pay taxes in any case.

    If you are ordering from outside the EU, your order may be subject to import duties and taxes, which are levied once a shipment reaches your country. The general amount of the duties and taxes fee is about 5-20% of the dollar amount of the merchandise. However, this is just a general guideline and may vary depending on the country to which the order was shipped. Bonfoton (Boncomp Oy) cannot control and is not responsible for any duties/taxes applied to your package. You will be responsible for paying additional charges for customs clearance. Customs policies vary widely from country to country; please contact your local customs office for further information. Note, in rare occasions, customs agents may delay delivery of some packages.

    Note, that the local FedEx customer support is happy assist you if needed. 



    Are there any product safety issues that I need to be aware of?

    The Bonfoton Camera Obscura Room Lens comes with eight small attachment plates that small children could swallow. The neodymium magnets that are glued to the Bonfoton Lens are not super strong but they might damage some magnet strips or electronics if they get in close contact.

    When attaching the BonfotonUP by using the suction cup option the safety rope is needed for most secure attachment. The BonfotonUP includes a large optical grade glass prism that can brake if handled poorly.

    The Bonfoton Camera Obscura Room Lens and the BonfotonUP are optically much weaker than average eyeglasses. They can project an image but are very poor in concentrating heat. Projection of any scenery is always cooler than the real scenery due to the products being unable to introduce any extra heat into the projection itself.

    You would need approximately 15 Bonfoton Camera Obscura Room Lenses in order to make an average magnifying glass.Here’s an approximate scale indicating the heat concentrating properties of some similar optical materials:

    Bonfoton Relative Optical strenghts

    Even though the Bonfoton Camera Obscura Lens and the BonfotonUP are weak in concentrating heat. They should not be used in direct sunlight.It is possible that the projection of the sun (the bright spot on the wall in direct sunlight) might discolour or fade paintings, wallpaper etc. objects in the room.

    Do not use the Bonfoton Camera Obscura Room Lens or the BonfotonUP in a room that stores flammable liquids.

    Do not use the BonfotonUP lenses without the prism head.

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