# Photography & Optics calculators

> Depth of field, hyperfocal distance, field of view, crop factor, exposure value and equivalent exposures, ND filters, megapixels and print size, telescope magnification, image file size, time-lapse, flash guide number.

12 calculators. HTML index: https://tttkmbb.com/photography · JSON: https://tttkmbb.com/api/v1/calculators?category=photography

- [Depth of Field Calculator](https://tttkmbb.com/photography/depth-of-field.md): Computes the near and far limits of acceptable sharpness, the total depth of field and the hyperfocal distance from focal length, f-number, focus distance and the sensor's circle of confusion, using the standard thin-lens depth-of-field equations. Tool: `calculate_depth_of_field`.
- [Hyperfocal Distance Calculator](https://tttkmbb.com/photography/hyperfocal-distance.md): Computes the hyperfocal distance H = f²/(N·c) + f for a focal length, f-number and sensor circle of confusion, the near limit obtained when focusing at H, and a table of H for the common apertures f/2.8–f/16. Tool: `calculate_hyperfocal_distance`.
- [Field of View Calculator](https://tttkmbb.com/photography/field-of-view.md): Computes the horizontal, vertical and diagonal angles of view of a rectilinear lens from its focal length and the sensor dimensions, and the width and height of the scene covered at a given subject distance. Tool: `calculate_field_of_view`.
- [Crop Factor Calculator](https://tttkmbb.com/photography/crop-factor.md): Computes a sensor's crop factor (43.27 mm full-frame diagonal ÷ sensor diagonal), its area relative to full frame, and the full-frame equivalent focal length and depth-of-field-equivalent aperture for a given lens. Tool: `calculate_crop_factor`.
- [Exposure Value Calculator](https://tttkmbb.com/photography/exposure-value.md): Computes the exposure value EV = log2(N²/t) of a camera setting, the ISO-100 normalised light value EV100, an illuminance estimate in lux (incident-meter calibration C = 250) and a description of the lighting the settings correspond to. Tool: `calculate_exposure_value`.
- [Equivalent Exposure Calculator](https://tttkmbb.com/photography/equivalent-exposure.md): Solves the shutter speed that keeps the exposure unchanged when the aperture and/or ISO are changed, using the reciprocity relation t2 = t1 × (N2/N1)² × (ISO1/ISO2), and reports the stop changes involved. Tool: `calculate_equivalent_exposure`.
- [ND Filter Exposure Calculator](https://tttkmbb.com/photography/nd-filter-exposure.md): Computes the shutter speed needed after adding a neutral-density filter given in stops or as a filter factor (ND8, ND64, ND1000 ...), plus the filter's optical density and a table of resulting shutter speeds for common filters. Tool: `calculate_nd_filter_exposure`.
- [Megapixels to Print Size Calculator](https://tttkmbb.com/photography/megapixels-print-size.md): Computes the megapixel count and aspect ratio of an image from its pixel dimensions and the print size it yields at a chosen resolution in dots per inch, with a table for 150, 200, 240 and 300 dpi. Tool: `calculate_print_size_from_megapixels`.
- [Telescope Magnification Calculator](https://tttkmbb.com/photography/telescope-magnification.md): Computes the magnification of a telescope and eyepiece combination (with optional Barlow), the exit pupil, true field of view, focal ratio, useful magnification range, Dawes and Rayleigh resolution limits and an estimated limiting magnitude. Tool: `calculate_telescope_magnification`.
- [Image File Size Calculator](https://tttkmbb.com/photography/image-file-size.md): Estimates the storage size of an image from its pixel dimensions, bits per channel, number of channels and a compression ratio, and scales the result to a number of images, in decimal megabytes and gigabytes. Tool: `estimate_image_file_size`.
- [Time-Lapse Calculator](https://tttkmbb.com/photography/time-lapse.md): Computes the number of frames, the shooting interval and the playback speed-up factor for a time-lapse from the real event duration, the desired clip length and the frame rate, plus storage needs from a per-frame file size. Tool: `calculate_time_lapse`.
- [Flash Guide Number Calculator](https://tttkmbb.com/photography/flash-guide-number.md): Scales a flash's guide number (quoted at ISO 100) to the working ISO with GN × √(ISO/100) and solves the guide-number equation GN = distance × f-number for the required aperture at a distance or the maximum flash range at an aperture. Tool: `calculate_flash_exposure`.